Mechanically expanding heart valve and delivery apparatus therefor

ABSTRACT

An assembly can comprise a radially expandable and compressible annular frame, at least one linear actuator assembly coupled to the frame and at least one locking mechanism coupled to the frame. The linear actuator can be configured to apply a distally directed force and/or a proximally directed force to the frame to radially expand or compress the frame. The locking mechanism can comprise a first sleeve member connected to the frame at a first location, a second sleeve member having internal threads and being connected to the frame at a second location, and a first screw configured to engage the internal threads of the second sleeve member to retain the frame in a radially expanded state.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Appl. No.62/430,810, filed Dec. 6, 2016, which is incorporated herein byreference in its entirety.

FIELD

The present disclosure relates to implantable, mechanically expandableprosthetic devices, such as prosthetic heart valves, and to methods anddelivery assemblies for, and including, such prosthetic devices.

BACKGROUND

The human heart can suffer from various valvular diseases. Thesevalvular diseases can result in significant malfunctioning of the heartand ultimately require repair of the native valve or replacement of thenative valve with an artificial valve. There are a number of knownrepair devices (e.g., stents) and artificial valves, as well as a numberof known methods of implanting these devices and valves in humans.Because of the drawbacks associated with conventional open-heartsurgery, percutaneous and minimally-invasive surgical approaches aregarnering attention. In one technique, a prosthetic device is configuredto be implanted in a less invasive procedure by way of catheterization.For example, a collapsible transcatheter prosthetic heart valve can becrimped to a compressed state and percutaneously introduced in thecompressed state on a catheter and expanded to a functional size at thedesired position by mechanical expansion or using a self-expanding frameor stent. Despite the recent advancements in percutaneous valvetechnology, there remains a need for improved transcatheter heart valvesand delivery devices for such valves.

SUMMARY

Embodiments of improved prosthetic implant delivery assemblies andframes therefor are disclosed herein, as well as related methods anddevices for such assemblies. In several embodiments, the disclosedassemblies are configured for delivering replacement heart valves into aheart of a patient.

In one aspect, the present disclosure provides a delivery assembly for aprosthetic implant. The delivery assembly can include a deliveryapparatus and a prosthetic valve that can include a radially expandableand compressible expandable frame and a plurality of locking unitscoupled to the frame. The delivery apparatus can include a plurality ofelongate positioning members releasably coupled to the locking units anda plurality of release members coaxially disposed with respect to, andengaged with, the locking units.

The positioning members can be moved axially to selectively expand orcontract the prosthetic valve. When the prosthetic valve has beenexpanded to a desired size, the release members can be retracted fromthe locking units, causing the locking units to lock the prostheticvalve in the expanded state and causing the positioning members todecouple from the frame of the prosthetic valve.

In one representative embodiment, a prosthetic valve delivery assemblycomprises a prosthetic valve and a delivery apparatus. The prostheticvalve can comprise a radially expandable and compressible expandableframe and a plurality of locking units coupled to the frame atcircumferentially spaced locations. Each locking unit can comprise arespective first coupling member and a locking member. The deliveryapparatus can comprise a plurality of elongate positioning members, eachof the positioning members comprising a respective second couplingmember at a distal end thereof, each second coupling member beingreleasably coupled to a respective first coupling member. The deliveryapparatus can further comprise a plurality of elongate actuationmembers, each of the actuation members extending coaxially through oneof the positioning members and having a distal end portion coupled tothe frame. The delivery apparatus can further comprise a plurality ofrelease members, each of the plurality of release members engaged with,such as extending over or through, one of the locking units. Moving thepositioning members or the actuation members axially relative to oneanother causes the frame to expand or contract. Retracting the releasemembers proximal to the locking members of the locking units causes thelocking members to move to a locked position to resist contraction ofthe frame and retracting the release members proximal to the firstcoupling members of the locking units causes the first coupling membersto decouple from the second coupling members, thereby permitting thepositioning members to decouple from the locking units.

In some embodiments, the handle can be coupled to proximal end portionsof the first and second actuation members. The handle can comprise afirst actuator configured to produce axial movement of the positioningmembers. In some embodiments, the handle can comprise a second actuatorconfigured to produce axial movement of the release members relative tothe positioning members and the actuation members.

In some embodiments, each of the locking members can comprise a pair ofdeflectable locking jaws disposed about one of the actuation members. Insome embodiments, each of the first coupling members can comprise a taband a notch and each of the second coupling members can comprise a taband a notch. The tab of the first coupling member can be received in thenotch of the second coupling member and the tab of the second couplingmember can be received in the notch of the first coupling member. Insome embodiments, the tab of the second coupling member can comprise anaxially extending slot.

In some embodiments, the actuation members can comprise a plurality oftethers. Ion some embodiments, a plurality of cutting members can beconfigured to sever the actuation members at locations proximal to thelocking units. In some embodiments, each of the actuation members cancomprise a plurality of longitudinally spaced apart protrusionsconfigured to engage one of the locking members of one of the lockingunits.

In some embodiments, each of the locking units can comprise an elongatefirst member coupled to a proximal end of the frame and an elongatesecond member coupled to a distal end of the frame. The first and secondmembers can be axially moveable relative to each other.

In some embodiments, each of the first members of the locking units canbe releasably coupled to one of the positioning members and each of thesecond members can be releasably coupled to one of the actuationmembers. In some embodiments, retracting the release members proximal tothe locking units can be effective to decouple the second members of thelocking units from the actuation members.

In some embodiments, each of the first members of the locking units cancomprise a first locking feature and each of the second members of thelocking units can comprise a second locking feature. In theseembodiments, retracting the release members proximal to the lockingunits can cause the first locking features to engage the second lockingfeatures to resist relative axial movement between the first and secondmembers and contraction of the frame.

In some embodiments, each of the first locking features can comprise adeflectable locking bar and each of the second locking features cancomprise at least one aperture sized to receive a locking bar. In someembodiments, the first member of each locking unit can be pivotablyconnected to an apex at the proximal end of the frame and the secondmember of each locking unit can be pivotably connected to an apex at thedistal end of the frame. In some embodiments, the frame can comprise aplurality of interconnected struts having a plurality of linear segmentsthat are laterally offset from each other in a direction perpendicularto the lengths of the struts.

In some embodiments, the struts can be connected to each other atlocations between the linear segments. In some embodiments, the strutscan be hingeably coupled to each other by pins extending through thestruts at the locations between the linear segments. In someembodiments, each of the actuation members can extend coaxially throughone of the positioning members. In some embodiments, each of the releasemembers can extend through one of the locking units and coaxiallybetween one of the positioning members and one of the actuation members.In some embodiments, the first coupling member of each of the pluralityof locking units can comprise a radially-outwardly biased fin andwherein each of the release members is disposed about a positioningmember and a first coupling member.

In another representative embodiment, a method of delivering aprosthetic valve comprises inserting a distal end of an elongatedelivery apparatus into a patient, wherein the elongate deliveryapparatus is releasably coupled to the prosthetic valve and theprosthetic valve comprises an expandable frame comprising a plurality oflocking units. The method further comprises axially moving a pluralityof elongate positioning members of the delivery apparatus to expand theprosthetic valve to an expanded state of a desired size, and removing aplurality of elongate release members from the plurality of lockingunits, causing the positioning members to decouple from the frame andthe locking units to lock the frame in the expanded state. The elongatedelivery apparatus can then be removed from the patient.

In some embodiments, removing the release members from the locking unitcan allow first coupling members of the actuation members to decouplefrom corresponding second coupling members of the locking units. In someembodiments, axially moving a plurality of elongate actuation members ofthe delivery apparatus can comprise axially moving a first plurality ofactuation members relative to a second plurality of actuation members ofthe delivery apparatus to expand the prosthetic valve, and removing therelease members from the locking units can allow the first and secondactuation members to decouple from the frame.

In another representative embodiment, a prosthetic valve comprises aradially expandable and compressible frame comprising a plurality ofinterconnected struts. Each strut has a first end, a second end, and alength extending from the first end to the second end. Each strut cancomprise a plurality of linear segments that are laterally offset fromeach other in a direction perpendicular to the lengths of the struts.The prosthetic valve can further comprise a valvular structure, such asa plurality of leaflets, mounted to the frame and configured to regulatethe flow of blood through the prosthetic valve.

In some embodiments, each of the plurality of struts is hingeablyconnected to at least another of the plurality of struts. In someembodiments, the prosthetic valve can further comprise a spacer disposedbetween a pair of connected struts. In some embodiments, the struts canbe connected to each other by pins extending through the struts. In someembodiments, the frame can comprise a plurality of circumferentiallyspaced locking units configured to lock the frame in a radially expandedstate.

In another representative embodiment, an assembly can comprise aprosthetic heart valve comprising a radially expandable and compressibleannular frame, at least one linear actuator assembly coupled to theframe and at least one locking mechanism coupled to the frame. The atleast one linear actuator assembly can be configured to apply a distallydirected force and/or a proximally directed force to the frame toradially expand or compress the frame. The at least one lockingmechanism can comprise a first sleeve member, a second sleeve member,and a first screw. The first sleeve member can be connected to the frameat a first location. The second sleeve member can have internal threadsand can be connected to the frame at a second location. The first screwcan be configured to engage the internal threads of the second sleevemember to retain the frame in a radially expanded state.

In some embodiments, the at least one linear actuator assembly can bereleasably coupled to the frame. In some embodiments, the at least onelinear actuator assembly can comprise an actuator member configured tobe releasably coupled to the frame.

In some embodiments, the at least one linear actuator assembly cancomprise a first threaded member connected to a distal end portion ofthe actuator member. The first threaded member can be configured toreleasably engage a second threaded member connected to the frame.

In some embodiments, the first threaded member can comprise a secondscrew and the second threaded member can comprise an internally threadednut. In some embodiments, the actuator member can comprise a cable. Insome embodiments, the at least one linear actuator assembly can furthercomprise a sleeve positioned annularly around the actuator member.

In some embodiments, the assembly can further comprise an annularstopper connected to the frame. In these embodiments, the actuatormember can extend through the stopper and the at least one linearactuator assembly can comprise a support tube positioned annularlyaround the actuator member and the stopper can be configured to engage adistal end of the support tube and prevent the support tube from movingdistally beyond the stopper in an axial direction.

In some embodiments, the assembly can further comprise a locking toolconfigured to be releasably coupled to the first screw. The locking toolcan comprise a tool head configured to engage and produce rotation ofthe first screw when the locking tool is coupled to the first screw suchthat the first screw moves axially through the first sleeve member andthe second sleeve member.

In some embodiments, the first screw can have a screw head at itsproximal end and the shape of the tool head can be configured tocorrespond to a shape of the screw head such that the tool head isoperable to couple with the screw head such that rotation of the toolhead causes rotation of the first screw.

In some embodiments, the screw head and the first sleeve member can beconfigured such that the screw head is prevented from moving distallybeyond the first sleeve member in an axial direction.

In some embodiments, the at least one locking mechanism can furthercomprise an inner shaft extending partly within a lumen of the toolhead. In these embodiments, the inner shaft can have a threaded surfaceat its distal end, the screw head can have internal threads, and theinner shaft can be configured such that its threaded surface engages theinternal threads of the screw head.

In some embodiments, the first screw can further comprise a rigidportion and a flexible portion positioned between the screw head and therigid portion. In some embodiments, the flexible portion of the firstscrew can comprise braded cable. In some embodiments, the flexibleportion of the first screw can comprise hypotube.

In some embodiments, the first screw can further comprise a rigidportion connected to the screw head, a flexible portion connected to adistal end of the rigid portion, and a stopper connected to a distal endof the flexible portion.

In some embodiments, the assembly can further comprise a spring lockattached to the first sleeve member. In these embodiments, the springlock can be configured to exert a radially inward directed force againstthe screw head to resist rotation of the screw.

In some embodiments, the assembly can further comprise a spring lockattached to the screw head. In these embodiments, the spring lock can beconfigured to exert a radially inward directed force against the firstsleeve member to resist rotation of the screw.

In some embodiments, the assembly can further comprise a flange attachedto the screw head. In these embodiments, the flange can be configured tobend against the first sleeve member to resist rotation of the screw.

In some embodiments, the assembly can further comprise a ratchet lockattached to a proximal end of the first sleeve member. In theseembodiments, the ratchet lock can comprise teeth configured to allowrotation of the screw head in a first direction and prevent rotation ofthe screw head in a second direction.

In some embodiments, the assembly can further comprise a click lockattached to a proximal end of the first sleeve member. In theseembodiments, the click lock can comprise teeth configured to resistrotation of the screw by an amount less than 90 degrees and to clickwhen the screw is rotated 90 degrees.

In another representative embodiment, an assembly can comprise aprosthetic valve comprising a radially expandable and compressibleannular frame and at least one expansion and locking mechanism. The atleast one expansion and locking mechanism can comprise a linear actuatorconnected to the frame and a rotating member. The linear actuator can beconfigured to apply a distally directed force and/or a proximallydirected force to the frame to radially expand or compress the frame.The rotating member can be coaxially positioned relative to the linearactuator and can be configured to retain the frame in a radiallyexpanded state.

In some embodiments, the assembly can further comprise a first sleevemember and a second sleeve member. In these embodiments, the firstsleeve member can be connected to the frame at a first location, thesecond sleeve member can have internal threads and can be connected tothe frame at a second location, the linear actuator can be releasablycoupled to the frame, the rotating member can be a screw configured toengage the internal threads of the second sleeve member, and the linearactuator can extend through a lumen of the screw.

In some embodiments, the assembly can further comprise a locking toolthat is configured to be releasably coupled to the screw and rotate thescrew such that the screw moves axially through the first sleeve memberand the second sleeve member when the locking tool is coupled to thescrew.

In some embodiments, the locking tool and the first sleeve member can beconfigured such that the locking tool is prevented from moving distallybeyond the first threaded member in an axial direction.

In some embodiments, the screw can have a screw head at its proximalend. In these embodiments, the screw head and the first member can beconfigured such that the screw head is prevented from moving distallybeyond the first sleeve member in an axial direction.

In some embodiments, the linear actuator can be an actuator screw havingexternal threads and can be connected to the frame at a first locationand the assembly can further comprise a sleeve connected to the frame ata second location. In these embodiments, the actuator screw can extendthrough a lumen of the sleeve, the rotating member can be a locking nuthaving internal threads configured to engage the threads of the actuatorscrew, and the sleeve and the locking nut can be configured such thatthe locking nut is prevented from moving distally beyond the sleeve inan axial direction.

In some embodiments, the actuator screw can comprise a first portion anda second portion. In these embodiments, a diameter of the second portioncan be less than a diameter of the first portion.

In some embodiments, the assembly can further comprise an annularactuator member having internal threads configured to engage the threadsof the second portion of the actuator screw such that when the internalthreads of the actuator member are engaged with the threads of thesecond portion of the actuator screw, axial movement of the actuatormember results in axial movement of the actuator screw.

In some embodiments, the assembly can further comprise a locking toolpositioned within a lumen of the sleeve. In these embodiments, thelocking tool can have a notched portion at its distal end configured toengage a corresponding notched portion at a proximal end of the lockingnut such that rotation of the locking tool in a clockwise directioncauses rotation of the locking nut in a clockwise direction.

In some embodiments, the locking tool can have an internally threadedsurface to engage the threads of the actuator screw. In someembodiments, the assembly can further comprise a support tube positionedannularly around the locking tool. In these embodiments, a proximal endof the sleeve can be configured to engage a distal end of the supporttube such that the support tube is prevented from moving distally beyondthe proximal end of the sleeve in an axial direction.

In some embodiments, the assembly can further comprise a skirt. In theseembodiments, the frame can comprise a plurality of rows of struts andthe skirt can be positioned inside of at least one row of struts andoutside of at least another row of struts.

In some embodiments, the assembly can further comprise a skirt. In theseembodiments, the frame can comprise a plurality of rows of struts andthe skirt can be positioned inside of at least one row of struts andoutside at least another row of struts.

In another representative embodiment, an implantable prosthetic valvecan comprise an annular frame and a skirt. The annular frame cancomprise a plurality of rows of struts and can be radially collapsibleand expandable between a radially collapsed configuration and a radiallyexpanded configuration. The skirt can be weaved around the struts suchthat the skirt is positioned inside of at least one row of struts andoutside of at least another row of struts.

In another representative embodiment, a method of implanting aprosthetic heart valve can comprise inserting the prosthetic heart valveinto a patient's vasculature, the prosthetic heart valve being coupledto a distal end portion of a linear actuator, wherein the prostheticheart valve comprises a frame in a radially compressed state, actuatingthe linear actuator to expand the frame to a radially expanded state,and rotating a screw to advance the screw through first and secondmembers on the frame to retain the prosthetic valve in the radiallyexpanded state.

In some embodiments, the act of rotating the screw can comprise rotatinga locking tool coupled to the screw and then de-coupling the lockingtool from the screw after the screw is advanced through the first andsecond members.

In some embodiments, the method can further comprise de-coupling thelinear actuator from the frame. In some embodiments, the act ofde-coupling the linear actuator can comprise unscrewing a threadedportion of the linear actuator from a corresponding threaded portion ofthe frame. In some embodiments, the act of actuating the linear actuatorcan comprise applying a proximally directed force to a distal portion ofthe frame with a cable.

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of an embodiment of a prosthetic valvedelivery assembly.

FIG. 2 is a side elevational view of a prosthetic valve, according toone embodiment.

FIGS. 3A and 3B are enlarged perspective views and side views,respectively, of an embodiment of coupled frame struts useable in theprosthetic valve of FIG. 2.

FIG. 4 is a side elevational view of another embodiment of a frame thatcan be used in the prosthetic valve of FIG. 2.

FIG. 5 is a side view of an embodiment of a strut for a frame of aprosthetic valve, such as the frame of FIG. 2, or the frame of the FIG.4.

FIG. 6 is a side view of the frame of FIG. 4 shown in a radiallycompressed state.

FIG. 7 is a side view of a prosthetic valve incorporating the frame ofFIG. 4 shown in a radially compressed state.

FIG. 8 is an enlarged perspective view of the distal end portion of theprosthetic valve delivery assembly of FIG. 1.

FIG. 9 is an enlarged side view of a locking unit and the distal endportion of a positioning member of the prosthetic valve deliveryassembly of FIG. 1.

FIG. 10A is an enlarged side view of the locking and the positioningmember of FIG. 9, illustrating the positioning member decoupled from thelocking unit.

FIG. 10B is enlarged side view of the distal end portion of thepositioning member of FIG. 10A rotated 90 degrees from the orientationshown in FIG. 10A.

FIG. 11 is an enlarged side view of the locking unit and the positioningmember of FIG. 9 rotated 90 degrees from the orientation shown in FIG.9.

FIG. 12A is a schematic diagram of an actuation member having lockingfeatures that can be used with the prosthetic valve delivery assembly ofFIG. 1, according to one embodiment.

FIG. 12B is a schematic diagram of another embodiment of an actuationmember having locking features that can be used with the prostheticvalve delivery assembly of FIG. 1.

FIG. 12C is a schematic diagram of another embodiment of an actuationmember having locking features that can be used with the prostheticvalve delivery assembly of FIG. 1.

FIG. 13 is an enlarged cross-sectional view of the handle of theprosthetic valve delivery assembly of FIG. 1.

FIG. 14 is a perspective view of a portion of a frame of a prostheticvalve incorporating an alternative implementation of a locking unit.

FIG. 15 is an enlarged side view of the locking unit of FIG. 14.

FIG. 16A is a cross-sectional view of the locking unit of FIG. 14 shownin the fully contracted state corresponding to the fully radiallyexpanded state of the prosthetic valve.

FIG. 16B is an enlarged cross-sectional view of a portion of the lockingunit shown in FIG. 16A.

FIG. 16C is a cross-sectional view of the locking unit of FIG. 16Ashowing a release member retracted to release the locking unit from thedelivery apparatus and lock the locking unit in the deployed state.

FIG. 16D is an enlarged cross-sectional view of a portion of the lockingunit shown in FIG. 16C.

FIG. 17A is an enlarged cross-sectional view of a portion of a lockingunit that can be used with the prosthetic valve delivery assembly ofFIG. 1, according to one embodiment, showing the locking unit portion ina locked configuration.

FIG. 17B is an enlarged cross-sectional view of the locking unit of FIG.17A, showing the locking unit in a release configuration.

FIG. 18 shows the distal end of another exemplary prosthetic valvedelivery system.

FIG. 19A shows a top view of the prosthetic valve delivery system ofFIG. 18.

FIG. 19B shows a top view of another embodiment of a prosthetic heartvalve delivery system.

FIG. 20A shows the frame of FIG. 18.

FIG. 20B shows the frame of FIG. 20A with a force exerted on the frame.

FIG. 20C shows the frame of FIG. 20A in a locked configuration.

FIG. 21 shows a portion of the delivery system of FIG. 18 with expansionmembers removed.

FIG. 22 shows a portion of the delivery system of FIG. 18 with lockingmembers in place.

FIG. 23A-23B show expanded views of the expansion mechanism.

FIGS. 24A-24D show expanded views of the locking mechanism.

FIG. 25A-25D show exploded views of the locking mechanism.

FIG. 26A-26B show various views of another exemplary expansion andlocking mechanism.

FIG. 27 is a perspective view of a prosthetic valve frame, shown in aradially collapsed state, having a plurality of expansion and lockingmechanisms, according to another embodiment.

FIG. 28 is a perspective view of the frame and the expansion and lockingmechanisms of FIG. 27, with the frame shown in a radially expandedstate.

FIG. 29A is a perspective view of a screw of one of the expansion andlocking mechanisms of FIG. 27.

FIG. 29B is a perspective view of one of the expansion and lockingmechanisms of FIG. 27.

FIG. 29C is another perspective view of the frame and the expansion andlocking mechanisms of FIG. 27, with the frame shown in a radiallyexpanded state.

FIG. 30 shows a cross sectional view of one of the expansion and lockingmechanisms of FIG. 27 along with a portion of the frame.

FIG. 31 is another perspective view of one of the expansion and lockingmechanisms of FIG. 27.

FIG. 32 shows an exemplary flexible screw that can be implemented in aprosthetic heart valve.

FIG. 33 shows a portion of the frame of a prosthetic valve locked inplace with a rigid screw.

FIG. 34 shows a portion of the frame of a prosthetic valve locked inplace with the flexible screw of FIG. 32.

FIG. 35 shows another exemplary flexible screw that can be implementedin a prosthetic heart valve.

FIG. 36A shows a portion of the frame of a prosthetic valve and theflexible screw of FIG. 35 prior to locking the valve in place.

FIG. 36B shows a portion of the frame of a prosthetic valve locked inplace with the flexible screw of FIG. 35.

FIGS. 37A-37C show alternative embodiments of a flexible screw that canbe implemented in a prosthetic heart valve.

FIG. 38 shows a portion of the frame of a prosthetic valve locked inplace with a screw.

FIGS. 39-41 show the frame and the screw of FIG. 38 with an exemplaryspring lock to prevent inadvertent rotation of the screw after the frameis locked.

FIGS. 42-43 show the frame and the screw of FIG. 38 with anotherexemplary spring lock.

FIGS. 44-45 show the frame and the screw of FIG. 38 with an exemplarypermanent bend lock.

FIG. 46 shows the frame and the screw of FIG. 38 with an exemplaryratchet lock.

FIGS. 47A-47D show various views of the ratchet lock of FIG. 46.

FIG. 48 shows the frame and the screw of FIG. 38 with a click lock.

FIGS. 49A-49D show various views of the click lock of FIG. 48.

FIG. 50 shows an alternative exemplary frame of a prosthetic heart valveand a skirt.

FIG. 51 is a perspective view of a prosthetic valve, according toanother embodiment.

FIGS. 52A-52F show various views of a strut for a frame of a prostheticvalve, such as the frame of FIG. 51. FIG. 52A is an elevation view ofthe outside of the strut. FIG. 52B is an elevation view of the inside ofthe strut. FIG. 52C is an end view of the strut. FIG. 52D is an end viewof the opposite end of the strut. FIGS. 52E-52F are top and bottom planviews of the strut, respectively.

FIGS. 53A-53D show various views of a frame of a prosthetic valve formedfrom multiple struts of the type shown in FIGS. 52A-52F. FIG. 53A is afront elevation view of the frame, which is symmetrical about a centrallongitudinal axis. FIG. 53B is a front elevation view of the frame withthe rear half of the frame removed for purposes of illustration. FIG.53C is a top plan view of the frame. The bottom plan view is a mirrorimage of the top plan view. FIG. 53D is a perspective view of the frame.

DETAILED DESCRIPTION

Described herein are examples of prosthetic implant delivery assembliesand components thereof which can improve a physician's ability tocontrol the size of a mechanically-expandable prosthetic implant, suchas prosthetic valves (e.g., prosthetic heart valves or venous valves),stents, or grafts, as well as facilitate separation of the prostheticimplant from the delivery assembly, during the implantation procedure.The present disclosure also provides frames for use with such prostheticimplants. The frames can comprise struts shaped to reduce or eliminatepinching of the soft components of the prosthetic implant (e.g.,leaflets of the implant) when the implant is radially compressed to adelivery configuration for delivery into a patient.

FIG. 1 shows an example of a prosthetic implant delivery assembly 10according to one embodiment of the present disclosure. The deliveryassembly 10 can include two main components: a prosthetic heart valve 14and a delivery apparatus 18. The prosthetic valve 14 can be releasablycoupled to the delivery apparatus 18, as further described below. Itshould be understood that the delivery apparatus 18 and other deliveryapparatuses disclosed herein can be used to implant prosthetic devicesother than prosthetic valves, such as stents or grafts.

FIG. 2 is a side elevational view of the prosthetic valve 14 shown inits deployed, radially expanded configuration. While only one side theprosthetic valve 14 is shown in the drawings, it should be appreciatedthat the opposite side is similar to the portion shown. The prostheticvalve 14 can include an annular stent or frame 22, and a valve structure24 which can be coupled to the frame 22. The frame 22 can have an inflowend portion 26, an intermediate portion 28, and an outflow end portion30. The prosthetic valve 14 can define a longitudinal axis extendingthrough the inflow end portion 26 and the outflow end portion 30.

The frame 22 can be made of any of various suitable materials, such asstainless steel or a nickel titanium alloy (“NiTi”), for exampleNitinol. The frame 22 can include a plurality of interconnected latticestruts 32 arranged in a lattice-type pattern and forming a plurality ofapices 34 at the outflow end 30 of the prosthetic valve 14. The struts32 can also form similar apices at the inflow end of the prostheticvalve (which are covered by a skirt 50 in FIG. 2). The lattice struts 32are shown as positioned diagonally, or offset at an angle relative to,and radially offset from, the longitudinal axis of the prosthetic valve.In other implementations, the lattice struts 32 can be offset by adifferent amount than depicted in FIG. 2, or some or all of the latticestruts 32 can be positioned parallel to the longitudinal axis of theprosthetic valve 14.

The lattice struts 32 can be pivotably coupled to one another. In theillustrated embodiment, for example, the end portions of the struts 32forming the apices 34 at the outflow end 30 and at the inflow end 26 ofthe frame 22 can have a respective opening 36. The struts 32 also can beformed with apertures 38 spaced apart along their lengths between theopposite ends of the struts. Respective hinges can be formed at theapices 34 and at the locations where struts 32 overlap each otherbetween the ends of the frame via fasteners 40, which can compriserivets or pins that extend through the apertures 36, 38. The hinges canallow the struts 32 to pivot relative to one another as the frame 22 isexpanded or contracted, such as during assembly, preparation, orimplantation of the prosthetic valve 14. For example, the frame 22 (andthus the prosthetic valve 14) can be manipulated into a radiallycompressed or contracted configuration (see, e.g., FIGS. 6 and 7) andinserted into a patient for implantation. Once inside the body, theprosthetic valve 14 can be manipulated into an expanded state (e.g.,FIGS. 2 and 4) and then released from the delivery apparatus 18 (e.g.,FIG. 1), as further described below.

The frame 22 can be formed using any suitable technique. Suitabletechniques can include separately forming individual components (e.g.,the struts 32 and fasteners 40) of the frame and then mechanicallyassembling and connecting the individual components to form the frame22. The struts and fasteners can be formed, for example, by lasercutting those components from sheets or tubes of metal, or byelectroforming (electroplating or electrodeposition) or physical vapordeposition. In some embodiments, electroforming or physical vapordeposition can be used to form subcomponents of the frame 22 or theentire frame 22 with pivotable connections between the struts. In oneimplementation, for example, electroforming or physical vapor depositioncan be used to form struts 32 having integral fasteners 40. Theindividual struts can be assembled together into a frame by insertingthe integral fasteners 40 of each strut through a corresponding apertureof an adjacent strut. In some embodiments, electroforming or physicalvapor deposition can be used to form the entire frame in its final,cylindrical shape. In other embodiments, electroforming or physicalvapor deposition can be used to form the entire frame in a flattenedconfiguration, after which the ends of the flattened frame are connectedto each other to form the final cylindrical shape of the frame.

In other embodiments, the lattice struts 32 are not coupled to eachother with respective hinges (e.g., fasteners 40) but are otherwisepivotable or bendable relative to each other to permit radial expansionand contraction of the frame. For example, the frame 22 can be formed(e.g., via laser cutting, electroforming or physical vapor deposition)from a single piece of material (e.g., a metal tube).

In addition to the lattice struts 32, the frame 22 can include one ormore longitudinally extending support struts 42. The support struts 42can be circumferentially spaced about the frame 22 and coupled,including being pivotably coupled, to the lattice struts 32. The supportstruts 42 can be positioned parallel to, and radially spaced apart from,the longitudinal axis of the prosthetic valve. The support struts 42 canenhance the rigidity of the frame 22 and help the frame 22 maintain auniform shape as it is expanded or contracted. In some implementations,the frame 22 does not include the support struts 42. The support struts42 can be connected to the lattice struts 32 at the hinge joints formedby fasteners 40 that can extend through respective apertures in thelattice struts and the support struts.

With reference to FIGS. 3A and 3B, a spacer 46, such as a washer orbushing, can be disposed in a joint between lattice struts 32, or ajoint between lattice struts 32 and support struts 42 (not shown). Whenthe lattice struts 32 and/or support struts 42 are pivotably coupled toone another, the spacers 46 can assist the lattice struts 32, or latticestruts 32 and support struts 42, in moving relative to one another. Thespacer 46 can also act to space the lattice struts 32 from one another,or from the support struts 42. In some implementations, the frame 22does not include the spacers 46, or the lattice struts 32, or latticestruts 32 and support struts 42, are spaced apart in a different manner.

In particular embodiments, the fasteners 40 do not extend radiallyoutwardly from their respective apertures 36, 38 in the struts and canbe contained completely within the apertures. As shown in FIG. 3B, forexample, each of the apertures 36 on the radially outermost struts 32can include a counter-bore or enlarged recessed portion 37 that is sizedto receive the head portion 41 of a respective fastener 40 (e.g., arivet). The head portion 41 can be received entirely within thecounter-bore 37 and does not extend radially outwardly from thecounter-bore, for example, the head portion 41 can be flush with theouter surface of the strut 32. Similarly, the apertures 38 also can beformed with counter-bores to receive the head portions 41 of thefasteners. In this manner, the fasteners 40 do not increase orcontribute to the overall crimp profile of the prosthetic valve and donot interfere with or place undue stresses on the delivery sheath of thevalve (e.g., sheath 82 in FIG. 1).

Returning to FIG. 2, the prosthetic valve 14 can include a valvularstructure 24 to regulate the flow of blood through the prosthetic valve.The valvular structure 24 can comprise, for example, a leaflet assembly48 comprising one or more leaflets made of a flexible material. Theleaflets of the leaflet assembly 48 can be made from in whole or part,biological material (e.g., pericardial tissue, such as bovine or equinepericardium), bio-compatible synthetic materials, or other suchmaterials, such as those described in U.S. Pat. No. 6,730,118, which isincorporated herein by reference.

The prosthetic valve can also include an annular skirt or sealing member50 that can be secured to the outer surface of the inflow end portion 26of the frame 22, for example, with sutures 56 adjacent the inflow endportion 26 of the frame 22. The inflow end portion of the leafletassembly 48 can be secured to the frame 22 and/or the skirt 50, forexample using sutures 56. The skirt 50 helps establish a seal with thenative tissue at the implantation site to prevent or minimizeperivalvular leakage. In alternative embodiments, the prosthetic valvecan have a skirt or sealing member mounted on the inside of the frame ora skirt or sealing member mounted on the inside and outside of theframe. The skirt can be formed from natural tissue (e.g., pericardialtissue) or any of various biocompatible synthetic materials, includingbiocompatible fabrics (e.g., polyethylene terephthalate (PET) fabric).

Further details regarding transcatheter prosthetic heart valves,including the manner in which the valve structure 24 can be coupled tothe frame 22 of the prosthetic valve 14, can be found, for example, inU.S. Pat. Nos. 6,730,118, 7,393,360, 7,510,575, 7,993,394, and8,652,202, which are incorporated herein by reference in theirentireties.

FIG. 4 is a side elevational view of a portion of a frame 200 that canbe used with a prosthetic valve in at least certain embodiments of thepresent disclosure. While only one side of the frame 200 is depicted inFIG. 4, it should be appreciated that the opposite side can be similarto the portion shown. The frame 200 is similar to the frame 22 discussedabove but does not include the longitudinal struts 42. The frame 200 caninclude a plurality of lattice struts 204. Each of the lattice struts204 can include a plurality of apertures 208. The apertures 208 can beused to connect the lattice struts 204 to one another using fasteners210, such as described above for the lattice struts 32 (FIG. 2). Inother implementations, the apertures 208 and fasteners 210 can beomitted. For example, the lattice struts 204 can be fixedly connected toone another, such as by welding or adhesion, or by laser-cutting theindividual struts of the frame from a metal tube. Although not shown inFIG. 4, a spacer may be included between the lattice struts 204, such asintermediate the portions of the lattice struts 204 having the apertures208. In a particular example, the spacers can be configured as describedabove for the spacer 46. Similarly, if desired, the frame 200 caninclude support struts (not shown) that can be analogous to the supportstruts 42 (FIG. 2).

As best shown in FIG. 5, each lattice strut 204 can have an offset, orzig-zag, pattern defined by a plurality of offset linear portions orsegments 218. The linear segments 218 in the illustrated embodiment arearranged end-to-end relative to each other with adjacent endsinterconnected to each other by intermediate segments 220. The strut 204can have enlarged end portions 224 that form the apices at the inflowand outflow end of the frame. Each linear segment 218 is slightlylaterally offset from an adjacent linear segment 218 in a directionperpendicular to the overall length of the strut 204 to provide thezig-zag pattern to the strut. Each of the intermediate segments 220 andend portions 224 can have a respective aperture 208 at its geometriccenter for receiving a fastener 210.

The amount of offset of each linear segment 218 relative to an adjacentlinear segment along the length of the strut 204 can be constant suchthat an imaginary line 214 can pass through the aperture 208 of eachintermediate segment 220 along the entire length of the strut. Inalternative embodiments, the amount of offset between two adjacentlinear segments 218 can vary along the length of the strut. For example,the amount of offset between linear segments 218 adjacent the outflowend of the frame can be greater than the amount of offset between linearsegments 218 adjacent the inflow end of the frame, or vice versa.

The linear segments 218 can include at least substantially flat orlinear opposing longitudinal edges 226 a, 226 b extending between curvedor rounded edges 228 of the intermediate segments 220. In alternativeembodiments, the opposing edges 228 of the intermediate segments 220 canbe substantially flat or linear edges that extend at an angle betweenrespective ends of the edges 226 a, 226 b of the liner segments 218.

As best shown in FIG. 5, the width W1 of each liner segment 218 isdefined as the distance measured between the opposing edges 226 a, 226 bof a segment 218. In the illustrated embodiment, the width W1 isconstant along the length of the strut 204. As such, each longitudinaledge 226 a is laterally offset from an adjacent longitudinal edge 226 aof an adjacent linear segment 218, and each longitudinal edge 226 b islaterally offset from an adjacent longitudinal edge 226 b of an adjacentlinear segment 218. The width W2 of each intermediate segment 220 andend portion 224 can be greater than the width W1 of the linear segments218.

In alternative embodiments, the width W1 of each linear segment 218 canvary along the length of a strut. For example, the width W1 of a linearsegment 218 adjacent the inflow end of the frame can be greater than thewidth W1 of a linear segment 218 adjacent the outflow end of the frame,or vice versa. Further, where the width W1 of the linear segments 218vary along the length of a strut 204, a linear segment can have onelongitudinal edge 226 a or 226 b that is collinear with a longitudinaledge of an adjacent linear segment on the same side of the strut, whilethe other longitudinal edge 226 a, 226 b is laterally offset from thelongitudinal edge of an adjacent linear strut on the same side of thestrut. In other words, the strut 204 can have an overall zig-zag oroffset pattern by virtue of the varying widths W1 of the linearsegments.

The offset, or zig-zag, pattern of the strut segments 218 can help spaceapart the struts 204 in the circumferential direction when the frame 200is in a radially compressed state, as shown in FIGS. 6 and 7. As shown,the open lattice structure of the frame 200 defining open cells 250between the struts 204 can be preserved even when the frame 200 is fullycompressed or contracted. For example, with reference to FIG. 6,although the width of the cells 250 along the length of the frame 200can vary between adjacent struts, a gap 256 remains at the middle of acell 250 between two adjacent pivot joints 254.

When the frame 200 is incorporated in a prosthetic valve (e.g., theprosthetic valve 14), the spaced-apart nature of the struts 204,including the gaps 256, can assist in protecting the soft components ofthe prosthetic valve as the frame 200 is expanded and contracted. FIG.7, for example, shows a prosthetic valve comprising the frame 200, askirt 266 mounted on the outside of the frame 200 and a leaflet assembly264 mounted inside of the frame 200. An inner skirt (not shown) also canbe mounted inside of the frame. The skirt 266 and leaflet assembly 264can be coupled to the frame 200, such as with sutures 270. The sutures270 can extend through the material of the skirt 266 and/or the leafletassembly 264 and radially about the struts 204. The gaps 256 created bythe offset configuration of the struts 204 can protect the leaflets 264,the skirt 266, and/or the sutures 270 from being pinched or shearedbetween adjacent struts 204 when the prosthetic valve is radiallycompressed. In this manner, the soft components of the prosthetic valveare protected against damage that can occur from contact with the metalstruts of the frame.

The delivery apparatus 18 of FIG. 1 is particularly suited forimplanting the prosthetic valve 14 or any of the other prosthetic valvesdisclosed herein. However, it should be noted that any of the prostheticvalves disclosed herein can be implanted using other suitable deliveryapparatuses. For example, any of the prosthetic valves disclosed hereincan be crimped over an inflatable balloon of a conventional ballooncatheter. Once delivered to the implantation site, the balloon can beinflated to expand the prosthetic valve to its fully functional size.

Referring again to FIG. 1, the delivery apparatus 18 can include ahandle 70, an elongate shaft 72 extending distally from the handle 70, aplurality of first actuation members 76 (also referred to as elongatepositioning members or actuator members), such as in the form ofpositioning tubes, extending through the shaft and distally outwardlyfrom a distal end 78 of the shaft 72, a plurality of release members 106(FIG. 9) extending through respective positioning members 76, and aplurality of second actuation members 86 (also referred to as “tethers”)extending through respective release members 106. The positioningmembers 76 can be at least partially disposed radially within, andextend axially through, one or more lumens of the shaft 72. For example,the positioning members 76 can extend through a central lumen of theshaft 72 or through separate respective lumens formed in the shaft 72.

The shaft 72 can have a distal end portion 82 that can function as asheath for containing or housing the prosthetic valve 14 in a radiallycompressed state for delivery through a patient's vasculature. In thisregard, the distal end portion 82 can have a lumen that is sized toreceive the prosthetic valve 14 in a radially compressed state. As shownin FIG. 13, the proximal end portion of the shaft 72 can extend into anaxially extending bore 138 formed in the distal end portion of thehandle 70. The proximal end portion of the shaft 72 can be retainedwithin the axial bore 138 through pressure or frictional contact withthe bore 138, using an adhesive, a clamp, a fastener, by thermallybonding the catheter 72 to the bore 138, or by some other technique ormechanism.

The positioning members 76 have distal end portions that can bereleasably connected to the prosthetic valve 14 via respectiverelease-and-locking units 94 (as best shown in FIG. 8). As shown in FIG.13, the positioning members 76 can extend through the shaft 72, andproximally beyond a proximal end 140 of the shaft, and into a centralbore 142 of the handle 70. A lead screw 144 can be disposed within thecentral bore 142 of the handle 70. The proximal ends of the positioningmembers 76 can be secured to the lead screw 144, such as being receivedwithin a bore (not shown) of the lead screw 144, where they can besecured by pressure or frictional contact with the bore of the leadscrew 144, using an adhesive, a clamp, a fastener, thermal bonding, oranother suitable technique or mechanism.

As shown in FIGS. 8 and 9, each actuation member 86 can extend through alumen of a respective positioning member 76. The actuation members 86can be coupled at their distal end portions to the distal end 60 of theframe 22. For example, the distal end portion of each actuation member86 can be connected to an apex 34 at the distal end 60 of the frame,such as by welding, an adhesive, or a mechanical fastener. Eachactuation member 86 can also extend through a lumen of a respectivelocking unit 94 that can be coupled to the frame 22, such as to an apex34 at a proximal end 62 of the frame. The actuation members 86 canextend proximally into and through the handle 70. Proximal end portions88 of the actuation members 86 can be releasably retained by a clampingmember 182 mounted in or on the handle 70 (FIG. 13).

The actuation members 86 function to apply a proximally directed pullingforce to the distal end 60 of the frame in cooperation with thepositioning members 76 that apply a distally directed pushing force tothe proximal end 62 of the frame to effect radially expansion of theframe 22. In particular embodiments, the actuation members 86 cancomprise a relatively flexible but relatively non-elastic material thatcan effectively transfer pulling forces generated at the handle 70 tothe distal end of the frame 22. For example, the actuation members 86can comprise wires, sutures, strings, or similar materials. In otherembodiments, the actuation members 86 can be relatively stiffercomponent, such as shaft or rod, that can transfer proximally directedpulling forces to the frame as well as distally directed pushing forcesto the frame.

The release members 106 have distal end portions 107 that extendcoaxially through respective locking units 94 (FIG. 9) and proximal endportions 108 that extend into the handle 70 (FIG. 13). The proximal endportions 108 of the release members 106 can extend through the leadscrew 144 and can be secured to a release knob 168 within the handle 70.

Referring to FIGS. 1 and 13, a threaded actuator nut 148 can be disposedabout the lead screw 144. Internal threads (not shown) of the threadedactuator nut 148 can engage threads 150 of the lead screw 144. An outersurface 152 of the threaded actuator nut 148 can extend through anaperture or window 154 formed in the outer surface 156 of the handle 70.The outer surface 152 of the threaded actuator nut 148 can include atexture, such as ridges 158, to aid a user in grasping and rotating thethreaded actuator nut 148.

Rotation of the threaded actuator nut 148 in a first direction can causethe lead screw 144 to translate axially in the distal direction relativeto the handle 70, thereby causing the positioning members 76 totranslate distally through the lumen of the shaft 72. Rotation of thethreaded actuator nut 148 in the opposite direction can cause the leadscrew 144 to translate proximally relative to the handle, therebycausing the positioning members 76 to retract or translate proximallythrough the lumen of the shaft 72.

In particular implementations, the number and spacing of the threads 150of the lead screw 144 (and thus the mating threads of the threadedactuator nut 148), and the axial length of the lead screw 144, can beselected to provide a desired degree of travel for the positioningmembers 76 and the release members 106. For example, the desired degreeof travel can be sufficient to allow the frame 22 (and thus theprosthetic valve 14) to be manipulated between a fully expanded state(such as shown in FIGS. 2 and 8) and a fully contracted or compressedstate (such as shown in FIGS. 6 and 7), including states in betweenbeing fully compressed or contracted and fully expanded, as furtherdescribed below.

The release-and-locking units 94 (also referred to as “locking units”)in the illustrated embodiment are configured to releasably connect thepositioning members 76 to the frame 22 of the prosthetic valve 14 and toselectively secure the actuation members 86 to retain the prostheticvalve 14 in a deployed and expanded state. With reference to FIGS. 8-11,the locking units 94 can comprise a generally cylindrical body 96, whichcan be secured to the frame 22 of the prosthetic valve 14 by a fastener130 (e.g., a pin or rivet). The fastener 130 can extend through anaperture 132 (FIG. 11) formed in the body 96 and through one or morecorresponding apertures 36 in the frame struts 32 forming the apices 34of the frame (FIG. 8).

The body 94 can comprise a locking feature, such as in the form of aclamp 98, disposed adjacent a distal end 100 of the locking unit 94 forselectively engaging an actuation member 86. The clamp 98 can comprise,for example, a pair of diametrically opposed jaws 102 that are biasedradially inwardly toward each other (as best shown in FIG. 11). Arelease member 106 can be disposed within a lumen of each locking unit94 to retain the jaws 102 of the clamp in a non-engaged or non-lockingstate during delivery of the prosthetic valve 14 (FIG. 9). Each releasemember 106 can extend proximally through a respective positioning member76 to the handle 70. As discussed above, the proximal end portions 108of the release members can be secured to a release knob 168 in thehandle (FIG. 13). Each actuation member 86 can extend proximally througha lumen of a respective release member 106 into the handle 70.

In particular implementations, the release members 106 can be made fromany suitable biocompatible metallic material or a polymeric material. Insome examples, the material can be selected to allow the release members106 to be easily moveable relative to the jaws 102 during valvedeployment, as further described below. For example, the release members106 can be made from a lubricious or low friction material (e.g., PTFE)or can have an outer layer made from a lubricious or low frictionmaterial (e.g., PTFE).

When the release members 106 are disposed within the locking units 94extending between the jaws 102, the jaws 102 are held in an unlockedstated and are prevented from contacting the actuation members 86. Inthe unlocked state, the actuation members 86 and the positioning members76 can move freely in the axial direction with respect to one another tocontrol radial expansion and compression of the prosthetic valve 14.When the prosthetic valve 14 is to be released from the deliveryapparatus 18, the release members 106 can be retracted proximallyrelative to the locking units 94 and the positioning members 76. Asshown in FIGS. 10A and 11, once the release members 106 are removed fromengagement with the jaws 102, the jaws 102 can move to a locked orengaged state engaging the actuation members 86, thus securing theactuation members 86 from further axial movement, thus retaining theframe 22 of the prosthetic valve 14 in a desired expanded state.

Referring back to FIG. 10, the locking units 94 can be releasablycoupled to the positioning members 76 by the release members 106. In theillustrated embodiment, for example, a distal end portion 110 of eachpositioning member 76 can include a coupling portion 112 that caninclude a tab 114 and a notch 116. Each locking unit 94 can include acorresponding notch 120 configured to receive the tab 114 of thepositioning member 76. Similarly, each locking unit 94 can include a tab122 to be inserted into, and received by, the notch 116 of a respectivepositioning member 76. The tabs 114,122 and notches 120, 116, along withthe release member 106, collectively can form a releasable, interlockingjoint. The engagement of the tabs 114, 122 with the notches 120, 116prevent axial separation of the positioning member 76 from the lockingunit 94, while the release member 106, which extends through the tabs114, 122 in the locked state, prevents lateral separation of thepositioning member 76 from the locking unit 94.

As shown in FIG. 10B, the tab 114 of the positioning member 76 caninclude an axially extending slot 128. The slot 128 can be sized toallow the tab 114 to be placed around the actuation member 86 or removedfrom the actuation member 86 by passing the actuation through the slot128. However, the slot 128 desirably is narrower than the diameter ofthe release member 106 to prevent lateral separation of the positioningmember 76 from the locking unit 94 when the release member 106 is in aposition extending through the tabs 114, 122 as depicted in FIG. 9. Asnoted above, retraction of the release member 106 from the jaws 102 ofthe clamp 98 allows the jaws to engage the actuation member 86. Furtherretraction of the release member 106 until the distal end of the releasemember 106 is proximal to the tab 122 and the notch 116 allows thedistal end portion 110 of the positioning member 76 to be separated fromthe locking unit 94 in a lateral direction (in a direction perpendicularto the length of the locking unit and the positioning member), asdepicted in FIG. 10A. As the positioning member 76 moves in a lateraldirection away from the locking unit 94, the actuation member 86 canpass through the slot 128 in the tab 114.

As further shown in FIG. 10A, the tabs 114, 122 can be formed withrespective inclined cam surfaces 124, 126, respectively, to facilitatethe separation of the positioning member 76 from the locking unit 94.Each cam surface 124, 126 is inclined relative to the longitudinal axisof the positioning member 76 at angle less than 90 degrees. As such,applying a proximally directed force to the positioning member 76 in thedirection of arrow 134 (such as by applying a pulling force to thepositioning member at handle 70) causes the positioning member 76 toslide laterally away from the locking unit 94 in the direction of arrow136.

The locking units 94 and/or the positioning members 76 can include acutting mechanism to cut the portions of the actuation members 86 thatextends proximally beyond the jaws 102 of the clamps 98 after theprosthetic valve is expanded and the release members are retracting toactuate the clamps. For example, a blade, or other cutting surface, canbe placed across the slot 128, such that the actuation members 86 can besevered when they pass through the slot 128 during lateral separation ofthe positioning member 76 away from the locking unit 94.

In another example, the locking units 94 can include a clamping memberthat can include cutting jaws (such as sharpened or serrated jaws)positioning proximal to the jaws 102. The cutting jaws, like the jaws102, can be retained in an open position away from the actuation memberby the release member 106. When the release member 106 is retracted outof engagement with the cutting jaws, the cutting jaws can deflectradially inwardly against the actuation member 86, thereby severing itat that location. In further examples, a separate cutting device can beused to sever the actuation members 86 at a desired location after thepositioning members 76 are released from the prosthetic valve 14, andoptionally, after the delivery apparatus 18 is removed from the body.

Referring again to FIGS. 1 and 13, the lead screw 144 includes anextension portion 160 that extends proximally from the threaded portionof the lead screw. The extension portion 160 can comprise two legportions 162 defining a U-shaped aperture or slot 164 between the legportions 162. The release knob 168 can comprise a slidable member 170disposed between the leg portions 162 and a user-engageable portion 172extending radially outwardly from the slidable member 170. The proximalend portions 108 of the release members 106 can be fixedly secured tothe slidable member 170, such as with a suitable adhesive, such thataxial movement of the slidable member 170 in the distal and proximaldirections causes corresponding movement of the release members.

The release knob 168 can be configured to be movable with, and alsoindependently of, the lead screw 144. As noted above, axial movement ofthe lead screw 144 causes corresponding movement of the positioningmembers 76. Thus, when the release knob 168 is retained relative to theextension portion 160 of the lead screw 144, axial movement of the leadscrew 144 causes the release knob 168 and the release members 106 tomove with the positioning members 76, such as during deployment andexpansion of the prosthetic valve. When the release knob 168 is notretained relative to the extension portion 160 of the lead screw 144,the release knob 168 can be translated axially relative to the extensionportion, thereby effecting axial movement of the release members 106relative to the positioning members 76 to actuate the clamping mechanism98 of the locking unit 94 and release the positioning members 76 fromthe frame 22 of the prosthetic valve.

Various mechanisms can be used to selectively and releasably retain therelease knob 168 axially relative to the extension portion 160 of thelead screw 144. For example, a moveable pin or similar mechanism can beinserted through the slidable member 170 and one or both leg portions162 of the extension portion 160 to retain the axial position of theslidable member 170 relative to the lead screw 144. Removing the pinfrom the slidable member 170 and/or the leg portions 162 allows axialmovement of the release knob 168 relative to the lead screw.

In another embodiment, the slidable member 170 can be configured to movebetween a first position where it is frictionally engaged by theextension portion 160 and a second position where the slidable member170 is no longer frictionally engaged by the extension portion 160. Inthe first position, the axial movement of the lead screw 144 causescorresponding movement of the release knob 168. In the second position,the release knob 168 can be moved axially independently of the leadscrew 144 in the distal and proximal directions.

The actuation members 86 can extend proximally beyond the proximal endportions 108 of the release members 106 and through an axially extendingbore or opening 178 formed in the proximal end portion 180 of the handle70. The actuation members 86 can be selectively secured relative to thehandle 70 using a clamping, or retaining, mechanism 182. The retainingmechanism 182 can comprise a plug member 184, a screw member 186connected at one end of the plug member 184, and knob 188 connected tothe opposite end of the screw member 186. The plug member 184 can bepositioned in a radially bore 184 formed in the proximal end portion 180of the handle 70. The plug member 184 can include a triangular ortrapezoidal lower surface that can be placed in, and removed from,contact with a corresponding shaped surface 192 of the radial bore 190.In other implementations, the plug member 184 can have a differentshape. The screw member 186 extends through a captured nut 194 such thatrotation of the knob 188 causes the plug member 184 to move toward oraway from the surface 192 of the radial bore 190.

When the knob 188 is fully tightened (such as by rotating the knob 188in a first direction), the lower surface of the plug member 184 canclamp the actuation members 86 against the surface 192, thereby securingthe actuation members 86 against movement relative to the handle 70, theshaft 72, the locking units 94, and the frame 22 of the prostheticvalve. When the knob 190 is rotated in the opposite direction, the plugmember 184 can move away from the surface 192 and the actuation members86, allowing the actuation members to move relative to the handle 70,the shaft 72, the locking units 94, and the frame 22 of the prostheticvalve.

To use the delivery apparatus 18 to delivery and implant the prostheticvalve 14 at a desired location within the heart (e.g., the native aorticvalve), the prosthetic valve 14 is connected to the positioning members76 using the locking units 94 and the release members 106, as shown inFIGS. 8 and 9. The release knob 168 is retained relative to the leadscrew 144 to prevent relative movement between the positioning members76 and the release members 106. The prosthetic valve 14 can then beradially compressed or crimped to a compressed state, as shown in FIG.7. The compressed prosthetic valve 14 can be loaded into the sheath 82of the shaft 72.

Conventional techniques and devices can be used to insert and advancethe delivery apparatus 18 and the prosthetic valve 14 through apatient's vasculature to the desired implantation site. For example, aprosthetic aortic valve can be delivered in a retrograde approach byadvancing the delivery apparatus through a femoral artery and the aortato the native aortic valve. At or adjacent the implantation site, theprosthetic valve 14 can be deployed from the sheath 82 by rotating theactuator nut 148 in a direction to cause the lead screw 144 to movedistally relative to the handle 70. This causes the positioning members76 and the release members 106 to move distally relative to the shaft72. The positioning members 76 push the prosthetic valve 14 distallyrelative to the shaft 72. The actuator nut 148 can be rotated until theprosthetic valve is deployed from the distal end of the sheath 82. Insome implementations, the inherent resiliently of the frame 22 may causethe prosthetic valve to at least partially expand when advanced from thesheath 82.

As the prosthetic valve 14 is deployed from the sheath 82, the retainingmechanism 182 can be in a release position allowing the actuationmembers 86 to move distally with the prosthetic valve. In this manner,the actuation members 86 do not apply any expansion forces to theprosthetic valve as it is being deployed from the sheath. To apply anexpansion force to the prosthetic valve, the retaining mechanism 182 istightened to retain the actuation members 86 relative to the handle 70.Continued rotation of the actuator nut 148 causes the positioningmembers 76 to continue to apply a distally directed force on theproximal end of the frame 22 while the actuation members 86 (which arenow restrained by the retaining mechanism 182) become taught and apply aproximally directed force on the distal end of the frame 22. Theapplication of these forces causes the frame 22 to foreshorten axiallyand expand radially.

In some embodiments, the retaining mechanism 182 can be kept in thelocked or engaged position against the actuation members 86 during valvedeployment so long as the actuation members are long enough and containenough slack to avoid applying any expansion force on the prostheticvalve as it is advanced from the sheath 82. For example, the lengths ofthe actuation members 86 can be selected to avoid applying any expansionforce on the prosthetic valve as it is advanced from the sheath 82 andafter the prosthetic valve is fully deployed from the sheath, theactuation members 86 become taught and begin to apply an expansion forceon the frame opposite the expansion force of the positioning members 76to expand the prosthetic valve.

If re-positioning or complete withdrawal of the prosthetic valve fromthe body is required, the user can rotate the actuator nut 148 in theopposite direction, which causes the positioning members 76 to pull theprosthetic valve back into the sheath 82. The action of the distal endportions 110 of the positioning members 76 being retracted into thesheath 82 causes the prosthetic valve to compress radially. If desiredor needed, the prosthetic valve can be partially compressed withoutbeing retracted into the sheath and then re-positioned and re-expandedby rotating the actuator nut 148. In some cases, the prosthetic valvecan be completely retracted back into the sheath 82 for re-positioningor complete withdrawal of the prosthetic valve from the body.

Once the prosthetic valve is expanded and positioned at the desiredlocation, the release members 106 can be retracted from the lockingunits 94. This can be accomplished by releasing the release knob 168from the lead screw 144 and retracting the release knob 168 proximally,which causes the release members 106 to retract relative to the lockingunits 94. When the distal ends of the release members 106 are proximalto the jaws 102 of the clamping mechanism 98, the jaws can engage theactuation members 86 to retain the prosthetic valve in the expandedstate. Further retraction of the release members 106 past the tabs 122of the locking units 94 allows the positioning members 76 to be releasedfrom the locking units. Retraction of the positioning members 76 byrotation of the actuator nut 148 or retracting the handle 70 causes thedistal end portions 110 of the positioning members to pull free of thelocking units 94. As discussed above, the portions of the actuationmembers 86 proximal to the clamping mechanisms 98 can be severed andremoved from the body. Thereafter, the delivery apparatus can bewithdrawn from the body.

In alternative embodiments, the distal end portions of the actuationmembers 86 can have locking features to promote locking engagement ofthe jaws 102 of the clamping mechanism 98 with the actuation members 86.FIGS. 12A, 12B, and 12C, for example, show actuation members 310, 320,330, respectively, that can be used with the locking unit 94 of FIG. 9.With reference to FIG. 12A, the actuation member 310 can include lockingfeatures in the form of a plurality of spaced-apart ribs or projections312 and slots 314 between adjacent ribs. The jaws 102 of the clamp 98can extend into the slots 314, helping secure the actuation member 86against movement relative to the clamp 98 in a direction opposite thetension being applied to the actuation member by the user. In otherwords, the actuation member 86 and the clamp 98 can function as aratchet that allows the actuation member 86 to be pulled through theclamp 98 in a first direction to expand the frame 22 but the engagementof the jaws 102 in the slots 314 resist movement of the actuation member86 in a second, opposite direction.

As shown in FIG. 12B, an actuation member 320 can include a plurality ofspaced-apart angled barbs 322 that can engage the jaws 102 of the clamp98. With reference to FIG. 12C, an actuation member 330 can include aplurality of spaced-apart spherical protrusions 332, such as beads, thatcan engage the jaws 102 of the clamp 98. The barbs 322 and theprotrusions 332, like the ribs 312, allow movement of the actuationmember through the jaws 102 in a first direction but resist movement ina second, opposite direction.

FIGS. 14, 15, and 16A-16D illustrate an alternative release-and-lockingunit 410 that can be used with a prosthetic implant delivery assembly,including, for example, the prosthetic implant delivery assembly 10 ofFIG. 1. The locking unit 410 can be incorporated in any radiallyexpandable frame of a prosthetic valve or other type of prostheticimplant, including, for example, the frame 22 of FIG. 2 or the frame 200of FIG. 4.

With reference to FIG. 14, the locking unit 410 can be coupled to aframe 412. The frame 412 can have a construction similar to the frame200. One or more locking units 410 can be coupled to the frame 412 atcircumferentially spaced apart locations, similar to the locking units94 described above. In particular embodiments, the frame 412 can havethree such locking units 412 coupled to the frame, in the manner shownin FIG. 1 with respect to the locking units 94.

The locking unit 410 generally can comprise an inner member 416, such aninner tubular member, and an outer member 418, such as an outer tubularmember, concentrically disposed about the inner member 416. The innermember 416 and the outer member can be moveable longitudinally relativeto each other in a telescoping manner to radially expand and contractthe frame 412, as further described below. As best shown in FIGS. 14 and16A, the inner member 416 can have a distal end portion 420 coupled to adistal end 422 of the frame 412 with a coupling element 424. The outermember 418 can have a proximal end portion 426 coupled to a proximal end428 of the frame 412 with a respective coupling element 424.

The inner member 416 and the outer member 418 can telescope relative toeach other between a fully contracted state (as shown in FIG. 15)corresponding to a fully radially expanded state of the prosthetic valveand a fully extended state (wherein the inner member 416 is fullyextended from the outer member 418) corresponding to a fully radiallycompressed state of the prosthetic valve. The locking unit 410 allowsthe prosthetic valve to be fully expanded or partially expanded todifferent diameters and retains the prosthetic valve in the partially orfully expanded state.

Each of the coupling elements 424 desirably is connected to a respectiveapex 430 at the proximal or distal end of the frame. Each apex 430 canbe formed by the adjacent end portions of two struts 432 that arepivotably connected to each other with a fastener 434 (e.g., a rivet orpin) that extends through corresponding apertures in the struts. Eachcoupling element 424 can be pivotably connected to a respective apex 430by a corresponding fastener 434 that extends into an opening or bore 436(FIG. 16A) of the coupling element 424. The fastener 434 in theillustrated embodiment therefore connects the end portions of the struts432 to a coupling element 424 while allowing the struts to pivotrelative to each other and the coupling element 424.

In alternative embodiments, the end portions of the struts 432 can besecured to each other and the coupling element without a pinnedconnection. For example, the frame can be laser cut from a metal tubewithout pinned connections at each apex and the coupling elements or theend portions of the inner and outer members 416, 418 can be connected tothe frame at or adjacent respective apices, such as by welding orsutures.

As further shown in FIG. 16A, a proximal end portion 438 of the innermember 416 can be releasably coupled to an inner actuation member, orshaft, 440 that extends the length of the delivery apparatus to a handleat the proximal end of the delivery apparatus (the handle is not shownbut can be similar to the handle 70 of FIG. 1). The proximal end portion426 of the outer member 418 can be releasably coupled to an outeractuation member, or shaft, 442 that extends the length of the deliveryapparatus to the handle at the proximal end of the delivery apparatus.The proximal end portions of the inner actuation member 440 and theouter actuation member 442 can be operatively connected to respectiveactuators or control mechanisms (e.g., rotatable or slidable knobs) inthe handle to effect longitudinal movement of the actuation members 440,442 relative to each other. The inner actuation member 440 can extendcoaxially through the outer actuation member 442. The pair of inner andouter actuation members 440, 442 can extend through an outer shaft (notshown, but can be similar to the shaft 72 of FIG. 1) along with otherpairs of inner and outer actuation members extending from the otherlocking units 410. All pairs of inner and outer actuation members 440,442 can be operatively connected to a common actuator or controlmechanism on the handle.

The inner and outer actuation members 440, 442, respectively, areconfigured to apply proximally and distally directed forces to the innerand outer members 416, 418, respectively, to effect radial expansion andcontraction of the frame 412. For example, to expand the frame, theouter actuation member 442 can be moved distally while the inneractuation member 440 is held stationary, thereby causing the outermember 418 to move distally over the inner member 416. As a result, adistally directed force is applied to the proximal end 428 of the frame412, causing the frame to foreshorten axially and expand radially.Expansion of the frame 412 can also be accomplished by moving the inneractuation member 440 proximally while the outer actuation member 442 isheld stationary. Alternatively, the frame 412 can be expanded by movingthe inner actuation member 440 proximally and simultaneously moving theouter actuation member 442 distally. The frame 412 can be radiallycontracted by reversing the direction of movement of the inner and outeractuation members 440, 442.

A release member 444 can extend coaxially between the inner actuationmember 440 and the outer actuation ember 442 along the length of thedelivery apparatus. A distal end portion 446 of the release member 444can extend coaxially between the inner member 416 and the outer member418 of the locking unit 410. The proximal end portion of the releasemember 444 (not shown) can be operatively connected to a correspondingactuator or control mechanism (e.g., a rotatable or slidable knob) onthe handle to effect longitudinal movement of the release memberrelative to the inner and outer actuation members 440, 442. The lockingunit 410 can include a centering tube 448 coaxially disposed between theinner member 416 and the outer member 418 distal to the release member444. The centering tube 448 helps maintain the outer member 418 incoaxial alignment with respect to the inner member 416 and can besecured, such as by welding, to the outer member 418. The proximal endportions of release members 444 extending from all locking units 410 onthe frame can be operatively connected to a common actuator or controlmechanism on the handle.

As noted above, the proximal end portion 426 of the outer member 418 canbe releasably coupled to the outer actuation member 442. As best shownin FIG. 15, the releasable coupling can be formed by, for example, anotch 454 and a tab 456 formed in the proximal end portion 426 of theouter member 418 and configured to releasably engage a corresponding tab458 and a notch 460 of the outer actuation member 442. During deliveryand expansion of the prosthetic valve, the release member 444 extendsthrough the notches 454, 460 and tabs 456, 458, and can prevent the tab456 from disengaging from the notch 460, and the tab 458 fromdisengaging from the notch 454, similar to the tabs 114, 120 and notches116, 120 of FIG. 10A. When the prosthetic valve is to be released fromthe delivery apparatus, the release member 444 can be moved proximallyof the notches 454, 460 and tabs 456, 458, allowing them to disengageand the outer member 418 and the outer actuation member 442 to disengageand decouple from each other.

The proximal end portion 438 of the inner member 416 can be releasablycoupled to the inner actuation member 440 in a similar fashion. Forexample, the inner member 416 can be coupled to the inner actuationmember 440 using a notch 462 and a tab 464 formed in the proximal endportion 438 of the inner member 416 and configured to releasably engagea corresponding tab 466 and a notch 468 of the inner actuation member440. During implantation and expansion, the release member 444 canextend coaxially over the notches 462, 468 and tabs 464, 466, preventingthe inner member 416 and the inner actuation member 440 decoupling. Whenthe prosthetic valve is to be released from the delivery apparatus, therelease member 444 can be moved proximally of the notches 462, 468 andtabs 464, 466, allowing them to disengage and the inner member 416 andthe inner actuation member 440 to disengage and decouple from eachother.

The inner and outer members 416, 418 can include corresponding lockingfeatures to retain the frame 412 in an expanded state. In theillustrated embodiment, for example, the inner member 416 can includeone or more longitudinally spaced apart apertures or recesses 470disposed along the length of the inner member 416. The apertures 470 canbe configured to receive a locking member 472 of the outer member 418.The locking member 472 can have a fixed end portion 474 secured to theouter member 418, a tapered or reduced-diameter intermediate portion476, and a free end portion, or latch portion, 478 configured to engageone of the recesses 470.

The locking member 472 can biased radially inwardly toward the innermember 416, such as by shape setting the locking member 472 to bendinwardly toward the inner member. In certain embodiments, for example,the locking member 472 (and, optionally, the entire outer member 422)can be formed from a shape-memory alloy, such as a nickel titanium alloy(“NiTi”), for example Nitinol. When the release member 444 is disposedbetween the inner member 416 and the outer member 418 during deliveryand expansion of the prosthetic valve, the locking member 472 isretained in an unlocked state with the latch portion 478 spaced radiallyoutward of the recesses 470 in the inner member 416 (as best shown inFIG. 16B). When the release member 444 is moved proximally beyond thelocking member 472, the locking member 472 can assume its pre-bentshape, indicated by position 480, and the latch portion 478 can extendinto a selected recess 470 (as best shown in FIG. 16D). Once the latchportion 478 has entered a recess 470, the inner member 416 and outermember 418 can be secured against relative axial movement therebyresisting radial contraction of the frame from its expanded state.

A rigid sleeve 490 can be mounted over the outer member 418 adjacent thelocking member 472 to resist buckling of the locking unit 410 in thearea of the locking member 472. The rigid sleeve 490 can be at leastgenerally annular and extend around at least a portion of the outersurface of the outer member 418. In some examples, the rigid sleeve 490can extend fully about the outer surface of the outer member 418. Inother examples, the rigid sleeve 490 can extend for less than the entireouter surface of the outer member 418. In some cases, the rigid sleeve490 can be fixedly secured to the outer member 418, such as by adhesionor welding.

In use, the prosthetic valve incorporating the frame 412 and lockingunits 410 can be placed in a compressed state in a sheath of a deliveryapparatus, as discussed above in connection with the prosthetic valve14. A physician can then insert the prosthetic valve into a patient.When the prosthetic valve is at the desired location within the patient,the physician can deploy the prosthetic valve from the sheath and thenexpand or contract the frame 412 to achieve a desired frame size(diameter) by manipulating the inner and outer actuation members 440,442, as described above. The prosthetic valve can be deployed from thesheath by retracting the sheath and/or by advancing the inner and outeractuation members in the distal direction to advance from the prostheticvalve from the sheath.

In particular embodiments, the prosthetic valve is fully functional oncedeployed from the sheath and at least partially expanded. In thismanner, the physician can test the operation of the prosthetic valveprior to releasing the prosthetic valve from the delivery apparatus. Ifneeded or desired, the prosthetic valve can be at least partiallyradially compressed, repositioned (e.g., repositioned superiorly orinferiorly) and then re-expanded. If needed or desired, the prostheticvalve can be fully radially compressed and retrieved back into thesheath of the delivery apparatus and withdrawn from the body.

When the desired size and position of the prosthetic valve has beenachieved, the physician can proximally retract the release member 444until it is located proximal to the locking member 472. The lockingmember 472 can then assume its pre-curved shape and engage an aperture470 in the inner member 416 of the locking unit, thereby resistingfurther relative movement between the inner member 416 and the outermember 418 and retaining the prosthetic valve in its expanded state. Asnoted above, the handle of the delivery apparatus can include commonactuator that controls retraction of all release members 444 extendingfrom corresponding locking units 410 on the frame in embodiments thatinclude plural locking units.

To release the prosthetic valve from the delivery apparatus, thephysician can further retract the release member 444 until it is locatedproximal to the notches 462, 468 and the tabs 464, 466 to de-couple theinner member 416 from the inner actuation member 440 and proximal to thenotches 454, 460 and the tabs 458, 456 to de-couple the outer member 418from the outer actuation member 442. Thereafter, the delivery apparatuscan be withdrawn from the body.

It should be appreciated that the locking units 410 and deliveryapparatus used therewith may be modified without departing from thescope of the present disclosure. For example, in some implementations,the outer member 418 can be axially moveable relative to a fixed innermember 416, in further implementations the inner member 416 can beaxially moveable relative to a fixed outer member 416, and in yet otherimplementations the inner member 416 and the outer member 418 may bothbe axially moveable relative to one another. Although the inner member416 is depicted and described as connected to a distal end 422 of theframe 412, in other implementations the position of the locking unit canbe reversed such that the inner member 416 can be connected to theproximal end 428 of the frame 412, and the outer member 418 connected tothe distal end 422 of the frame 412.

Similarly, the inner member 416 is described as having apertures 470 andthe outer member as having a locking member 472. However, in otherimplementations, the locking member 472 can be included on the innermember 416 and the apertures 470 can be formed in the outer member 422.Although depicted and described as tubular, the inner member 416, theouter member 418, and the release member 444 can have other shapes orconfigurations. For example, in one particular implementation, the innermember 416, the outer member 418, and the release member 444 can beformed from flat strips of material, with one of the inner member 416and the outer member 418 having the apertures 470 and the other havingthe locking member 472. The flat strips forming the inner member 416,the outer member 418, and the release member 444 can be housed in anelongated housing, such as a shaft or tubular member.

The frames and/or delivery assemblies of the present disclosure canprovide a number of advantages. For example, a mechanically expandableframe as described herein can be radially compressed to a deliveryconfiguration and loaded into a delivery apparatus without using acrimping apparatus. Because the frame can be fully expanded or expandedto a desired size less than the fully expanded state, at least in someembodiments, a prosthetic valve as described herein can be implanted invarious size annuluses, and the optimal size of the prosthetic valve canbe achieved during implantation. In some cases, a delivery assembly ofthe present disclosure can apply a sufficient expansion force to open orenlarge a calcified native valve, which can reduce or eliminate the needfor pre- or post-balloon valvuloplasty.

In addition, as noted above, the prosthetic valve can be fullyfunctional during the implantation procedure, which can reduce orprevent blood flow occlusion and avoid the use of rapid pacing duringimplantation. The embodiments disclosed herein also can allow for slowdeployment of the prosthetic valve, which can allow for tissue stressrelaxation, and can reduce the risk of aortic rupture.

FIGS. 17A and 17B illustrate a proximal portion of an alternativerelease-and-locking unit 502 (“locking unit”) that can be used inembodiments of the present disclosure, such as with the deliveryapparatus 18 of FIG. 1, to release a prosthetic valve from a deliveryapparatus and/or lock the prosthetic valve in its expanded state. One ormore such units 502 can be mounted on the frame of a prosthetic valve atcircumferentially spaced apart locations.

In some implementations, a distal portion of the locking unit 502, (notshown; the distal portion being to the left of the portion shown inFIGS. 17A and 17B), can be at least generally similar to a distalportion of the locking unit 94 of FIGS. 8, 9, 10A, 10B, and 11, and canincluding a locking feature, such as the clamp 98, and the aperture 132for receiving the fastener 130 for securing the locking unit 504 to avalve frame. In further implementations, a distal portion of the lockingunit 502 can be at least generally similar to a distal portion of thelocking unit 410 of FIGS. 14, 15, and 16A-16D.

The locking unit 502 can have an elongate, inner body or shaft 504(e.g., a generally cylindrical tube or shaft), which can be disposedwithin a lumen of a release member 510. A positioning member 516 canalso be disposed within the lumen of the release member 510. The innerbody 504 can be secured to the frame of the prosthetic valve. In someembodiments, the unit 502 can function solely as a release unit torelease the prosthetic valve from the delivery apparatus, in which casethe prosthetic valve can have another mechanism for locking the frame ofthe prosthetic valve in its expanded state.

The release member 510 and the positioning member 516 can be at leastgenerally similar to, respectively, the release member 106 of FIG. 9, orthe release member 444 of FIG. 16C, and the positioning member 76 ofFIG. 1. In at least certain embodiments, such as when the locking unit502 includes a distal portion similar to that of the locking unit 94,the locking unit can include an actuation member 520, which can be atleast generally similar to the actuation member 86 of FIG. 8. Theactuation member 520 can be disposed within a lumen of the body 504 ofthe locking unit 502 and a lumen of the positioning member 516. In otherembodiments, such as when the locking unit 502 includes a distal portionsimilar to that of the locking unit 410, the actuation member 520 can beomitted.

A proximal end portion 522 of the body 504 of the locking unit 502 cancomprise a radially-inwardly extending fin, or in-turned lip portion526. The fin 526 can be negatively angled, that is, the fin 526 isangled distally toward the prosthetic valve (to the left in thedrawings). The fin 526 can be configured to abut or extend into anangled notch or recessed portion 530 formed in a distal end portion 532of the positioning member 516. The fin 526 and an extension portion 524of the body 504 adjacent the fin can incorporate a preset bend, suchthat they are biased radially outwardly. For example, the locking unit502, or at least the fin 526 and the extension portion 524, can beformed from a shape-memory alloy, such as a nickel titanium alloy(“NiTi”), for example Nitinol.

The body 504 and the fin 526 can be heat set to provide a desired degreeof bending. When positioned within the release member 510, the fin 526and the extension portion 524 are radially constrained, and the fin isheld in contact with the notch 530. By virtue of the diameter or widthof the notch 530 increasing in a distal direction along the length ofthe positioning member 516, and the fin 526 being negatively angled, thefin and notch can engage each other to prevent axial separation of thepositioning member 516 from the inner body 504, thereby maintaining theconnection between the prosthetic valve and the delivery apparatus. Whenthe prosthetic valve is to be released from the delivery apparatus(e.g., the delivery apparatus 18), such as after being deployed within apatient's heart, the release member 510 can be retracted proximally, asshown in FIG. 17B. No longer being constrained by the release member510, the fin 526 and the extension portion 524 the body 504 of thelocking unit 502 can assume their preset shape, deflecting radiallyoutwardly, thus disengaging the fin from the notch 530. With the fin 526released from the notch 530, the locking unit 502 and the positioningmember 516 can decouple, thereby releasing the prosthetic valve from thedelivery apparatus and allowing the delivery apparatus to be removedfrom the patient.

FIG. 18 shows an alternative embodiment of a prosthetic valve deliveryassembly 600. The delivery assembly 600 can include a prosthetic valve602. The prosthetic valve 602 can include a radially expandable andcollapsible frame 604 and a valvular structure 606 supported inside theframe (FIGS. 19A and 19B). The frame 604 can be constructed in a mannersimilar to the frame 22 of FIG. 2 and can be formed from a plurality ofinterconnected struts similar to struts 32. The valvular structure canbe constructed in a manner similar to the valvular structure 24 of FIG.2.

The delivery assembly 600 can further include one or more linearactuator assemblies 608 and one or more locking mechanisms 610 securedto the frame 602. The one or more linear actuator assemblies 608 areconfigured to radially expand and compress the frame 604 and the one ormore locking mechanisms 610 are configured to lock or retain the frame604 in a particular radially expanded state as explained in more detailbelow. The delivery assembly 600 can further include one or more lockingtools 611 configured to advance the one or more locking mechanisms 610into a position to lock the frame 604 as explained in more detail below.

In the illustrated embodiment of FIG. 18, the delivery assembly 600includes two linear actuator assemblies 608 and one locking mechanism610. FIG. 19A shows an embodiment of the delivery assembly 600 havingtwo linear actuator assemblies 608 and one locking mechanism 610. FIG.19B shows an alternative embodiment of a prosthetic valve deliveryassembly 600′ that is the same as delivery assembly 600 except thatdelivery assembly 600′ has one linear actuator assembly 608 and twolocking mechanisms 610. In other embodiments, a prosthetic deliveryassembly can have any number of linear actuator assemblies and/orlocking mechanisms.

The delivery assembly 600 can be used to percutaneously implant theprosthetic valve 602 into a patient's vasculature to a desiredimplantation site, such as the native aortic valve. During implantation,the frame 604 is in a radially collapsed state, similar to the frame 200of FIG. 2. Once the prosthetic valve prosthetic valve 602 reaches thedesired implantation site, the one or more linear actuator assemblies608 can be used to radially expand the frame 604. Once the frame 604 isexpanded to a desired radially expanded size, the one or more lockingtools 611 can be used to position the one or more locking mechanisms 610to lock the frame 604 at that radially expanded size such that the frame604 is prevented from further radial expansion and/or contraction. Theone or more linear actuator assemblies 608 and the one or more lockingtools 611 can then be disconnected from the prosthetic valve 602 suchthat the frame 604 remains locked in a radially expanded state and thedisconnected portion of the delivery assembly 600 can be removed fromthe patient. The operation of the linear actuator assemblies 608, thelocking mechanisms 610, and the locking tools 611 are described morefully below.

FIG. 23A shows a linear actuator assembly 608 in the process of beingdisconnected from the frame 604 after the frame has been radiallyexpanded. Referring to FIG. 23A, the linear actuator assembly 608 caninclude an inner actuator member 612 (which can also be referred to asan actuation member), a cover tube 614 extending co-axially over theactuator member 612, a support tube or pusher member 616 extendingco-axially over the cover tube 614, a threaded screw 618, and a stopper620 fixedly mounted on the frame 604. FIG. 23B shows a perspective viewof the linear actuator assembly 608 without the support tube 616. Theactuator member 612 can be, for example, a rod, cable, or wire. Theactuator member 612 can be connected at its distal end to the threadedscrew 618 such that rotation of the actuator member 612 causes rotationof the threaded screw 618. The proximal end of the actuator member 612can be connected to a handle or other control device (not shown) that adoctor or operator of the delivery assembly 600 can use to rotate theactuator member 612. Similarly, the proximal ends of each cover tube 614and each support tube 616 can be connected to the handle.

The screw 618 has an externally threaded surface that can engage aninternally threaded surface of a nut or sleeve 622, which is affixed tothe frame 604, such as at the distal end of the frame. In the presentdisclosure, a “nut” is sometimes used generically to refer to a sleevethat does not necessarily have internal threads. Thus, reference to anut does not necessarily require internal threads unless the contextdictates otherwise. When the actuator member 612 is rotated to screw thescrew 618 into the nut 622, the actuator member 612 becomes connected tothe distal end of the frame 604 such that proximal or distal motion ofthe actuator member 612 causes proximal or distal motion, respectively,of the distal end of the frame 604.

The cover tube 614 annularly surrounds the actuator member 612. Thecover tube 614 can be connected to the actuator member 612 such that theactuator member 612 and the cover tube 614 rotate together and moveaxially together. The actuator member 612 and the cover tube 614 extendthrough the stopper 620, which can be affixed to a proximal end of theframe. The support tube 616 annularly surrounds the cover tube 614. Thestopper 620 has an annular inner surface with an inner diameter largerthan the outer diameter of the cover tube 614 and the screw 618 suchthat the cover tube 614 and the screw 618 can be retracted through thestopper 620 as the frame 604 is expanded and once the actuator isdisconnected from the frame, as further discussed below. The stopper 620is sized to abut or engage the distal end of the support tube 616 suchthat the support tube 616 is prevented from moving distally beyond thestopper 620.

In operation, prior to implantation in a patient, the screw 618 isthreaded into the actuator nut 622, thereby connecting the linearactuator assembly 608 to the frame 604. The frame 604 can then be placedin a radially collapsed state and the delivery assembly 600 can beinserted in a patient. Once the prosthetic valve 602 is at a desiredimplantation site, the frame 604 can be radially expanded as describedherein.

To radially expand the frame 604, the support tube 616 is held firmlyagainst the stopper 620. The actuator member 612 is then pulled in aproximal direction through the support tube 616, such as by pulling onthe proximal end of the actuator member 612 or actuating a control knobon the handle that produces proximal movement of the actuator member612. Because the support tube 616 is being held against the stopper 620,which is connected to the proximal end of the frame 604, the proximalend of the frame 604 is prevented from moving relative to the supporttube 616 and the handle. As such, movement of the actuator member 612 ina proximal direction results in movement of the distal end of the frame604 in a proximal direction causing the frame 604 to foreshorten axiallyand expand radially. FIG. 20A shows the frame 604 in a partiallyexpanded state, while FIG. 20B shows the frame 604 in a further expandedstate when a proximally directed force is applied to the distal end ofthe frame 604 while the proximal end of the frame 604 is held in place.In the illustrated embodiment, there is a one-to-one ratio between axialmovement of the actuator member 612 and the increase in the diameter ofthe frame 604, which allows for stable and controlled expansion of theframe.

It should be understood that the frame 604 can also be radially expandedby pushing the proximal end of the frame toward the distal end of theframe by pushing the support tube 616 against the stopper 620 whilekeeping the actuator member 612 stationary relative to the handle, oralternatively, by simultaneously pushing the support tube 616 distallyagainst the stopper 620 and pulling the actuator member 612 proximally.

After the frame 604 is expanded to a desired radially expanded size, thelocking mechanism 610 can be actuated to lock the frame 604 in thedesired radially expanded size, as discussed in further detail below,and the linear actuator assembly 608 can be disconnected from the frame604 as described herein. To disconnect the linear actuator assembly 608from the frame 604, the actuator member 612 can be rotated so as tounscrew the screw 618 from the nut 622. The actuator member 612 and thecover tube 614 can then be retracted proximally through the stopper 620and the linear actuator assembly 608 (including the actuator member 612,the screw 618, the cover tube 614, and the support tube 616) can bewithdrawn from the patient. The cover tube 614 facilitates passage ofthe screw 618 through the stopper 620. FIG. 21 shows the deliveryassembly 600 after the linear actuator assemblies 608 have been removed.In embodiments that have more than one linear actuator assembly 608, theabove procedure for expanding the frame 604 is performed for each linearactuator assembly 608.

Locking the frame 604 at a particular radially expanded state can beachieved using the locking mechanism 610 and the locking tool 611.Referring to FIG. 18 and FIGS. 24A-24D, the locking mechanism 610 caninclude a locking screw 624 having an externally threaded surface. Thelocking mechanism 610 can further include a proximal sleeve or nut 626(also referred to as a “proximal sleeve member”) and a distal sleeve ornut 628 (also referred to as a “distal sleeve member”) connected to theframe 604 at axially spaced apart locations. The proximal nut 626 can beconnected to a proximal end of the frame 604 and the distal nut 628 canbe connected to the frame 604 at a location axially aligned and distallyspaced from the proximal nut 626. The distal nut 628 can have internalthreads that can engage the external threads of the locking screw 624 toconnect the locking screw 624 to the frame 604 and prevent radialcontraction of the frame 604, as explained below. The proximal nut 626can be sized such that the locking screw 624 can slide freely within alumen of the proximal nut. In alternative embodiments, the proximal nut626 can have internal threads that can engage the external threads ofthe locking screw 624 to connect the locking screw 624 to the frame 604.

The locking screw 624 can have a screw head 630 at its proximal endhaving, for example, a square or rectangular shape. The screw head 630can be sized such that the screw head cannot advance distally beyond theproximal nut 626. The locking tool 611 can be configured to operate thescrew 624 after the prosthetic valve is expanded to a desired size viathe liner actuators. The tool 611 can comprise an elongated shaft 634and a tool head 632 connected to the distal end of the shaft 634. Theproximal end of the shaft 634 (not shown) can be connected to the handleof the delivery assembly 600, which can have an actuator (e.g., a knobon the handle) configured to rotate the shaft upon actuation by a user.The shaft 634 can comprise, for example, a rod or cable that hassufficient torsional rigidity to transfer torque from the proximal endof the shaft to the tool head 632.

The tool head 632 can have a square or rectangular opening 633corresponding to the shape of the screw head 630 such that the screwhead 630 can be received within the tool head 632. When the screw head630 is received within the tool head 632, rotation of the tool head 632causes rotation of the screw head 630. In alternative embodiments, thescrew head 630 and the opening of the tool head 632 can have variousother non-circular shapes that allow the tool head 632 to rotate thescrew head 630 when the tool head engages the screw head.

Referring to FIGS. 25B-25C, the shaft 634 can comprise an outer shaftand the tool 632 can further comprise an inner shaft 636 (e.g., a rod orcable) that extends coaxially through the outer shaft 634. A distal endportion of the inner shaft 636 extends into the tool head 632 and mountsan attachment member 638 configured to form a releasable connection withthe screw head 630. In the illustrated embodiment, for example, theattachment member 638 comprises external threads 640 that are configuredto engage internal threads 642 of an annular bore formed in the screwhead 630 so as to connect the inner shaft 636 to the screw head 630. Theinner shaft 636 can extend proximally to a handle or other device that adoctor or other operator of the delivery assembly 600 can use to rotatethe inner shaft 636. The inner shaft 636 can be rotated independently ofthe outer shaft 634 and the tool head 632.

Prior to implantation, the tool 611 can be attached to the locking screw624 by placing the tool head 632 around the screw head 630 as shown inFIG. 25C. The inner shaft 636 is then rotated in a first direction(e.g., in a clockwise direction) to screw the attachment member 638 intothe screw head 630 as shown in FIG. 25B. By retaining the inner shaft636 relative to the outer shaft 634 in the axial direction, theattachment of the attachment member 638 with the screw head 630maintains the engagement of the tool head 632 with the screw head 630.

The locking screw 624 can be initially positioned within the proximalnut 626 but not threaded into the distal nut 628. This allows the frameto be radially expanded by the linear actuator assemblies 608. Thedelivery assembly 600 can then be inserted into a patient and theprosthetic valve 602 can be expanded to a desired radial size asdescribed above. In other embodiments, the screw 624 need not bepre-inserted into the nut 626 and instead can be positioned on the frame604 such that when the screw is rotated, the screw extends into theproximal nut 626 and the distal nut 628. In other embodiments where theproximal nut 626 has internal threads, the screw 624 can be initiallythreaded into the proximal nut 626 but not the distal nut 628. In otherembodiments, the screw 624 need not be pre-mounted on the frame whilethe prosthetic valve is advanced to the implantation site. For example,the screw 624 can be separately delivered to the prosthetic valve (e.g.,using the tool 611) after the prosthetic valve is expanded at theimplantation site.

Once the prosthetic valve 602 is radially expanded to a desired size,the outer shaft 634 can be rotated (e.g., in a clockwise direction) torotate the tool head 632, which in turn rotates the locking screw 624and advances the distal end portion of the screw 624 through the distalnut 628, as shown in FIG. 24B. The locking screw 624 can be distallyadvanced such that the screw head 630 abuts the proximal nut 626. Whenso advanced, the threads of the locking screw 624 engage internalthreads of the distal nut 628. With the screw 624 connected to thedistal nut 628 and the screw head 630 abutted against the proximal nut626, the screw is prevented from further distal movement with respect tothe frame 604, thereby preventing contraction of the frame 604 fromoutside forces acting on the frame 604.

However, because the screw 624 can move freely within the proximal nut626, the proximal end of the screw can move in a proximal directionafter the screw is put in a locked position (engaging distal nut 628),thereby allowing additional expansion of the frame 604, either by usingthe linear actuator assembly 608 as described above or by continuing torotate the screw 624 after the screw head 630 abuts against the proximalnut 626. This can allow a physician to further expand the frame 604during implantation of the prosthetic valve 602 after advancing thelocking screw 624 to a locked position. This can also allow a physicianto expand the frame 604 days, months, or years later following theimplantation procedure when implanting a new prosthetic valve within thepreviously implanted prosthetic valve in a valve-in-valve procedure. Ifneeded, the previously implanted valve can be expanded using avalvuloplasty balloon prior to implanting the new prosthetic valve.

Anatomical forces only apply a compression force on the prosthetic valve602 once implanted and as such, there is no risk of spontaneousexpansion after the valve 602 is locked with the locking screw 624.After additional valve expansion is performed, the locking screw 624 canbe rotated to distally advance the screw such that the screw head 630abuts the proximal nut 626 to again put the screw into a lockedposition. In embodiments where the proximal nut 626 has internal threadsthat engage the locking screw 624, any radial contraction and expansionof the prosthetic valve 602 is prevented once the screw is inserted intonuts 626, 628, except from rotation of the screw.

Once the locking screw 624 is screwed into the distal nut 628 such thatthe screw head 630 abuts against the proximal nut 626, the inner shaft636 can be rotated in a second direction (e.g., a counter-clockwisedirection), as shown in FIG. 24C, to disconnect the attachment member638 from the screw head 630, as shown in FIG. 25C. The tool head 632 canthen be pulled back and removed from the screw head 630 as shown inFIGS. 24D and 25D so as to disconnect the locking tool 611 from thelocking screw 624 on the prosthetic valve. The disconnected locking tool611 can then be removed from the patient (e.g., when withdrawing thelinear actuator assemblies 608 if the linear actuator assemblies and thelocking tool are connected to a common handle), leaving the lockingscrew 624 connected to the frame 604 with the frame 604 locked in aparticular radially expanded state as shown in FIG. 22.

FIGS. 26A and 26B show cross-sectional views of expansion and lockingmechanism 700, according to another embodiment. The expansion andlocking mechanism 700 can be used to both radially expand and lock aprosthetic valve in a radially expanded state, such as prosthetic valve602. Therefore, an alternative embodiment of a prosthetic valve deliveryassembly can be the same as delivery assembly 600 with one or more ofthe linear actuator assemblies 608 and one or more of the lockingmechanisms 610 replaced with one or more expansion and lockingmechanisms 700. For example, instead of delivery assembly 600 of FIG.19A with two linear actuator assemblies 608 and one locking mechanism610 or delivery assembly 600′ of FIG. 19B with one linear actuatorassembly 608 and two locking mechanisms 610, a delivery assembly canhave three expansion and locking mechanisms 700. In other embodiments,the delivery assembly 600 or the delivery assembly 600′ can have anynumber of linear actuator assemblies 608 and/or locking mechanisms 610replaced by expansion and locking mechanisms 700. Example deliveryassemblies can have any number of expansion and locking mechanisms 700.

FIG. 26A shows the expansion and locking mechanism 700 and the frame 604when the frame is in a radially collapsed or crimped configuration andFIG. 26B shows the expansion and locking mechanism 700 and the frame 604when the frame is in a radially expanded configuration. As explainedabove, a delivery assembly may have multiple expansion and lockingmechanisms but only one is shown in FIGS. 26A-26B for purposes ofillustration.

The expansion and locking mechanism 700 can include a proximal nut orsleeve 702, a distal nut or sleeve 704, and an actuator nut 706 affixedto the frame 604. The nuts 702, 704, 706 can be axially spaced apartfrom each other along the length of the frame 604. The distal nut 704and the actuator nut 706 can have internal threaded surfaces. Inalternative embodiments, the proximal nut 702 can also have an internalthreaded surface. The proximal nut 702 can be affixed to a relativelyproximal portion of the frame 604, the actuator nut 706 can be affixedto a relatively distal end of the frame, and the distal nut 704 can beaffixed to the frame 604 at a location axially between the proximal nut702 and the actuator nut 706.

The expansion and locking mechanism 700 can further include an actuatormember 708 (which functions as a linear actuator or a push-pull memberin the illustrated embodiment), an actuator screw 710, a support tube712, a locking tool 714, and a locking screw 716. The actuator member708 can be, for example, a rod, a cable, or wire. The actuator member708 can be connected at its distal end to the actuator screw 710 suchthat rotation of the actuator member causes rotation of the actuatorscrew 710. The proximal end of the actuator member 708 can be connectedto a handle or other control device (not shown) that a doctor oroperator of the delivery assembly utilizing the expansion and lockingmechanism 700 can use to rotate the actuator member 708. Similarly theproximal ends of the support tube 712 and the locking tool 714 can beconnected to the handle.

The actuator screw 710 has an externally threaded surface that canengage with the internally threaded surface of the actuator nut 706.When the actuator member 708 is rotated to screw the screw 710 into theactuator nut 706, the actuator member 708 becomes connected to thedistal end of the frame 604 such that proximal or distal motion of theactuator member causes proximal or distal motion, respectively, of thedistal end of the frame.

The locking screw 716 annularly surrounds the actuator member 708 suchthat the actuator member extends through a lumen of the screw. Thelocking screw 716 has an externally threaded surface that can engage theinternally threaded surface of the distal nut 704. The locking screw 716can move in an axial direction within a lumen of the proximal nut 702and the actuator member 708 can move freely in an axial direction withrespect to the locking screw 716. The locking screw 716 has a screw head718 at its proximal end and the screw can lock the frame 604 in aparticularly radially expanded state as explained in further detailbelow.

In the illustrated embodiment, the threads of the locking screw 716 canbe sized to engage the internal threads of the proximal nut 702 suchthat the locking screw 716 can move distally and proximally relative tothe proximal nut 702 upon rotation of the locking screw 716. In otherembodiments, the threads of the locking screw 716 can be spaced inwardlyof the threads of the proximal nut 702 such the threads of the screw donot engage the threads of the nut, in which case the locking screw 716can be slid proximally and distally relative to the proximal nut, atleast until the locking screw 716 engages the distal nut 704.

The support tube 712 annularly surrounds a proximal portion of thelocking screw 716. The support tube 712 and the proximal nut 702 aresized such that the distal end of the support tube abuts or engages theproximal end of the proximal nut 702 such that the support tube 712 isprevented from moving distally beyond the proximal nut.

The locking tool 714 can be configured to be releasably coupled to thescrew head 718 of the locking screw 716 and to operate the locking screw716 after the prosthetic valve is expanded to a desired size via theactuator member 708 as explained below. The distal end of the lockingtool 714 can be coupled to the screw head 718 such that rotation of thelocking tool advances the locking screw 716 through the proximal nut 702and screws the locking screw 716 into the distal nut 704. The distal endof the locking tool 714 and the screw head 718 can have various shapesthat allow the locking tool to rotate the locking screw 716 when thelocking tool engages the screw. The locking tool 714 can be decoupledfrom the locking screw 716 after the screw has been screwed into thedistal nut 704.

In operation, prior to implantation, the actuator member 708 is threadedinto the actuator nut 706 and the locking screw 716 is positioned withinthe proximal nut 702 but is not threaded into the distal nut 704. Theframe 604 can then be placed in a radially collapsed state and thedelivery assembly 600 can be inserted in a patient. Once the prostheticvalve 602 is at a desired implantation site, the frame 604 can beradially expanded as described herein.

To radially expand the frame 604, the support tube 712 is held firmlyagainst the proximal nut 702. The actuator member 708 is then pulled ina proximal direction through the locking screw 716, such as by pullingon the proximal end of the actuator member 708 or actuating a controlknob on the handle that produces proximal movement of the actuatormember 708. Because the support tube 712 is being held against theproximal nut 702, which is connected to a proximal end of the frame 604,the proximal end of the frame 604 is prevented from moving relative tothe support tube 712 and the handle. As such, movement of the actuatormember 708 in a proximal direction results in movement of the distal endof the frame 604 in a proximal direction causing the frame 604 toforeshorten axially and expand radially. FIG. 26A shows the frame 604 ina radially collapsed state, while FIG. 26B shows the frame in a radiallyexpanded state.

It should be understood that the frame 604 can also be radially expandedby pushing the proximal end of the frame toward the distal end of theframe by pushing the support tube 712 against the proximal nut 702 whilekeeping the actuator member 708 stationary relative to the handle, oralternatively, by simultaneously pushing the support tube 712 distallyagainst the proximal nut 702 and pulling the actuator member 708proximally.

After the frame 604 is expanded to a desired radially expanded size, thelocking screw 716 can be actuated to lock the frame 604 in the desiredradially expanded size. Locking the frame 604 at a particular radiallyexpanded state can be achieved by using the locking tool 714 to advancethe locking screw 716 distally and screw the locking screw 716 into thedistal nut 704 until the screw head 718 abuts against the proximal nut702. This will cause the threads of the locking screw 716 to engage theinternal threads of the distal nut 704. When the screw head 718 alsoabuts against the proximal nut 702, the screw 716 cannot be advanced anyfurther in a distal direction, thereby preventing radially compressionof the frame 604. However, because the screw 716 can be moved relativeto the proximal nut 702 in a proximal direction after the frame 604 islocked, further expansion of the frame 604 is possible, either duringinitial implantation procedure or later during a valve-in-valveprocedure.

Further expansion of the frame can be achieved by pulling the lockingscrew 716 proximally to move the distal nut 704 toward the proximal nut702 (if the locking screw 716 is sized to slide freely within theproximal nut 702). Alternatively, if the locking screw 716 is sized toengage the threads of the proximal nut 702, the locking screw 716 can beunscrewed from the distal nut 704, which then allows further expansionof the frame by retracting the actuator member 708.

Once the frame 604 is locked in a radially expanded state, the lockingtool 714 can be decoupled from the locking screw 716 and the actuatormember 708 can be rotated so as to unscrew the screw 710 from theactuator nut 706. The actuator member 708, the support tube 712, and thelocking tool 714 can then be removed from the patient, leaving thelocking screw 716 connected to the frame 604 with the frame 604 lockedin a particular radially expanded state.

FIGS. 27-28 show another embodiment of a prosthetic valve comprising theframe 604 and expansion and locking mechanisms 800 (with the leafletsand other soft components removed for purposes of illustration). As withexpansion and locking mechanism 700, expansion and locking mechanism 800can be used to both radially expand and lock the prosthetic valve in aradially expanded state. As such, an alternative embodiment of aprosthetic valve delivery system can be the same as delivery assembly600 with one or more of the linear actuator assemblies 608 and one ormore of the locking mechanisms 610 replaced with one or more expansionand locking mechanisms 800. In the example of FIGS. 27 and 28, threeexpansion and locking mechanisms 800 are attached to the frame 604 butin other example delivery assemblies, any number of expansion andlocking mechanisms 800 can be used. FIG. 27 shows the expansion andlocking mechanisms 800 attached to the frame 604 when the frame is in aradially collapsed configuration and FIG. 28 shows expansion and lockingmechanisms attached to the frame when the frame is in a radiallyexpanded configuration. FIGS. 53A-53D are various views of the bareframe 604 with other components of the prosthetic valve removed forpurposes of illustration. FIGS. 52A-52F are various views of one of thestruts of the frame.

Referring to FIGS. 29A-29C, the expansion and locking mechanism 800 inthe illustrated embodiment can include an actuator screw 802 (whichfunctions as a linear actuator or a push-pull member in the illustratedembodiment) comprising a relatively long upper, or distal, portion 804and a relatively shorter lower, or proximal, portion 806 at the proximalend of the screw 800, wherein the lower portion has a smaller diameterthan the upper portion. Both the upper and lower portions 804, 806 ofthe screw 802 can have externally threaded surfaces.

The actuator screw 800 can have a distal attachment piece 808 attachedto its distal end having a radially extending distal valve connector810. The distal attachment piece 808 can be fixed to the screw 802(e.g., welded together or manufactured as one piece). The distal valveconnector 810 can extend through an opening at or near the distal end ofthe frame 604 formed at a location on the frame where two or more strutsintersect as shown in FIG. 29C. The distal valve connector 810 can befixed to the frame 604 (e.g., welded). Due to the shape of the struts,the distal end of the frame 604 comprises an alternating series ofdistal junctions 650 and distal apices 652. In the illustrated example,the distal valve connectors 810 of the three expansion and lockingmechanisms 800 are connected to the frame 604 through distal junctions650. In other examples, one or more distal valve connectors 810 can beconnected to the frame 604 through distal apices 652. In otherembodiments, the distal valve connectors 810 can be connected tojunctions closer to the proximal end of the frame 604.

The expansion and locking mechanism 800 can further include a sleeve812. The sleeve 812 can be positioned annularly around the upper portion806 of the screw 802 and can contain axial openings at its proximal anddistal ends through which the screw 802 can extend. The axial openingsand the lumen in the sleeve 812 can have a diameter larger than thediameter of the upper portion 806 of the screw 802 such that the screwcan move freely within the sleeve (the screw 802 can be moved proximallyand distally relative to the sleeve 812). Because the actuator screw 802can move freely within the sleeve, it can be used to radially expandand/or contract the frame 604 as disclosed in further detail below.

The sleeve 812 can have a proximal valve connector 814 extendingradially from its outer surface. The proximal valve connector 814 can befixed to the sleeve 812 (e.g., welded). The proximal valve connector 814can be axially spaced from the distal valve connector 810 such that theproximal valve connector can extend through an opening at or near theproximal end of the frame 604. The proximal end of the frame 604comprises an alternating series of proximal junctions 660 and proximalapices 662. In the illustrated example, the proximal valve connectors814 of the three expansion and locking mechanisms 800 are connected tothe frame 604 through proximal junctions 660. In other examples, one ormore proximal valve connectors 814 can be connected to the frame 604through proximal apices 662. In other embodiments, the proximal valveconnectors 814 can be connected to junctions closer to the distal end ofthe frame 604.

It should be understood that the distal and proximal connectors 810, 814need not be connected to opposite ends of the frame. The actuator 800can be used to expand and compress the frame as long as the distal andproximal connectors are connected to respective junctions on the framethat are axially spaced from each other.

A locking nut 816 can be positioned inside of the sleeve 812 and canhave an internally threaded surface that can engage the externallythreaded surface of the actuator screw 802. The locking nut 816 can havea notched portion 818 at its proximal end, the purpose of which isdescribed below. The locking nut can be used to lock the frame 604 intoa particularly radially expanded state, as discussed below.

FIG. 30 shows a cross sectional view of the expansion and lockingmechanism 800 including delivery components not shown in FIGS. 29A-29C.Referring to FIG. 30, the expansion and locking mechanism 800 canfurther include a support tube 820, an actuator member 822, and alocking tool 824. The proximal end of the support tube 820 can beconnected to a handle or other control device (not shown) that a doctoror operator of the delivery assembly utilizing to operate the expansionand locking mechanism 800 as described herein. Similarly, the proximalends of the actuator member 822 and the locking tool 824 can beconnected to the handle.

The support tube 820 annularly surrounds a proximal portion of thelocking tool 824 such that the locking tool extends through a lumen ofthe support tube. The support tube 820 and the sleeve are sized suchthat the distal end of the support tube abuts or engages the proximalend of the sleeve 812 such that the support tube is prevented frommoving distally beyond the sleeve.

The actuator member 822 extends through a lumen of the locking tool 824.The actuator member 822 can be, for example, a shaft, a rod, a cable, orwire. The distal end portion of the actuator member 822 can bereleasably connected to the lower portion 806 of the actuator screw 802.For example, the distal end portion of the actuator screw 802 can havean internally threaded surface that can engage the external threads ofthe lower portion 806 of the actuator screw 802. Alternatively, theactuator member can have external threads that engage an internallythreaded portion of the screw. When the actuator member 822 is threadedonto the actuator screw 802, axial movement of the actuator membercauses axial movement of the screw.

The distal portion of the locking tool 824 annularly surrounds theactuator screw 802 and extends through a lumen of the sleeve 812 and theproximal portion of the locking tool annularly surrounds the actuatormember 822 and extends through a lumen of the support tube 820 to thehandle of the delivery device. The locking tool 824 can have aninternally threaded surface that can engage the externally threadedsurface of the locking screw 802 such that clockwise orcounter-clockwise rotation of the locking tool 824 causes the lockingtool to advance distally or proximally along the screw, respectively.

The distal end of the locking tool 824 can comprise a notched portion826, as can best be seen in FIG. 31. The notched portion 826 of thelocking tool 824 can have an engagement surface 827 that is configuredto engage a correspondingly shaped engagement surface 819 of the notchedportion 818 of the locking nut 816 such that rotation of the lockingtool (e.g., clockwise rotation) causes the nut 816 to rotate in the samedirection (e.g., clockwise) and advance distally along the locking screw802. The notched portions 818, 826 in the illustrated embodiment areconfigured such that rotation of the locking tool 824 in the oppositedirection (e.g., counter-clockwise) allows the notched portion 826 ofthe tool 824 to disengage the notched portion 818 of the locking nut816; that is, rotation of the locking tool in a direction that causesthe locking tool to move proximally does not cause correspondingrotation of the nut.

In alternative embodiments, the distal end portion of the locking tool824 can have various other configurations adapted to engage the nut 816and produce rotation of the nut upon rotation of the locking tool formoving the nut distally, such as any of the tool configurationsdescribed herein. In some embodiments, the distal end portion of thelocking tool 824 can be adapted to produce rotation of the nut 816 inboth directions so as move the nut distally and proximally along thelocking screw 802. For example, the distal end portion of the lockingtool 824 can have the configuration of tool 634 shown in FIGS. 25A-25D.

In operation, prior to implantation, the actuator member 822 is screwedonto the lower portion 806 of the actuator screw 802 and the locking nut816 is rotated such that it is positioned at the proximal end of thescrew. The frame 604 can then be placed in a radially collapsed stateand the delivery assembly 600 can be inserted into a patient. Once theprosthetic valve is at a desired implantation site, the frame 604 can beradially expanded as described herein.

To radially expand the frame 604, the support tube 820 is held firmlyagainst the sleeve 812. The actuator member 822 is then pulled in aproximal direction through the support tube, such as by pulling on theproximal end of the actuator member or actuating a control knob on thehandle that produces proximal movement of the actuator member. Becausethe support tube 820 is being held against the sleeve 812, which isconnected to a proximal end of the frame 604 by the proximal valveconnector 814, the proximal end of the frame is prevented from movingrelative to the support tube. As such, movement of the actuator member822 in a proximal direction causes movement of the actuator screw 802 ina proximal direction (because the actuator member is threaded onto thescrew), thereby causing the frame 604 to foreshorten axially and expandradially. Alternatively, the frame 604 can be expanded by moving thesupport tube 820 distally while holding the actuator member 822stationary, or moving the support tube distally while moving theactuator member 822 proximally.

After the frame 604 is expanded to a desired radially expanded size, theframe can be locked at this radially expanded size as described herein.Locking the frame can be achieved by rotating the locking tool 824 in aclockwise direction causing the notched portion 826 of the locking toolto engage the notched portion 818 of the locking nut 816, therebyadvancing the locking nut distally along the actuator screw 802. Thelocking tool 824 can be so rotated until the locking nut 816 abuts aninternal shoulder at the distal end of the sleeve 812 and the lockingnut 816 cannot advance distally any further (see FIG. 31). This willprevent the screw 802 from advancing distally relative to the sleeve 812and radially compressing the frame 604. However, in the illustratedembodiment, the nut 816 and the screw 802 can still move proximallythrough the sleeve 812, thereby allowing additional expansion of theframe 604 either during implantation or later during a valve-in-valveprocedure.

Once the frame 604 is locked in radially expanded state, the lockingtool 824 can be rotated in a direction to move the locking toolproximally (e.g., in a counter-clockwise direction) to decouple thenotched portion 826 from the notched portion 818 of the locking nut 816and to unscrew the locking tool from the actuator screw 804.Additionally, the actuator member 822 can be rotated in a direction tounscrew the actuator member from the lower portion 806 of the actuatorscrew 802 (e.g., the actuator member 822 can be configured to disengagefrom the actuator screw when rotated counter-clockwise). Once thelocking tool 824 and the actuator member 822 are unscrewed from theactuator screw 804, they can be removed from the patient along with thesupport tube 820, leaving the actuator screw and the sleeve 812connected to the frame 604, as shown in FIG. 29C, with the frame 604locked in a particular radially expanded state.

In an alternative embodiment, the locking tool 824 can be formed withoutinternal threads that engage the external threads of the actuator screw802, which can allow the locking tool 824 to be slid distally andproximally through the sleeve 812 and along the actuator screw 802 toengage and disengage the nut 816.

Any of the delivery assemblies disclosed herein can have various handleconfigurations with one or more actuators or controls configured toproduce movement of components of the assembly that expand and compressa prosthetic valve (or another type of implant). In some embodiments,such as shown in FIGS. 1 and 13), the handle can have actuators that aremanually operated by a user by manually rotating and/or manuallypushing/pulling actuators on the handle. In other embodiments, theactuators on the handle and/or other components of the assembly can beelectrically, pneumatically and/or hydraulically controlled.

For example, in some embodiments, the handle can house one or moreelectric motors that are actuated by a user to produce movement ofcomponents of the delivery assembly, such as one or more motors operableto produce linear movement of the actuator screws 802, and one or moremotors operable to produce rotational movement of the locking tools 824(for rotating locking nuts 816). In one specific implementation, oneelectric motor is used to produce linear movement of all of theactuators screws 802 mounted on the prosthetic valve and one electricmotor is used to produce rotational movement of all of the locking tools824 included in the assembly. In another implementation, one electricmotor can be provided for each actuator screw and for each locking tool824. Further details regarding handle configurations that includeelectric motors for controlling delivery assembly components aredisclosed in U.S. Publication No. 2014/0296962, which is incorporatedherein by reference.

Additionally, any of the delivery assemblies disclosed herein caninclude software and/or hardware operable to control expansion of aprosthetic valve, as further disclosed in U.S. Publication No.2014/0296962. In particular embodiments, a delivery assembly can includea programmable controller (such as housed in the handle) that isoperable to radially expand a prosthetic valve according to a specificalgorithm. For example, a delivery assembly can include one or moremotors (e.g., electric motors) that are controlled by an electroniccontroller to radially expand a prosthetic valve according to a specificalgorithm. In certain implementations, for example, the controller canbe programed to produce pulsatile radial expansion of a prostheticvalve, as further disclosed in U.S. Publication No. 2014/0296962.

FIG. 32 shows an exemplary flexible screw 900 that can be used toreplace any of the screws described herein such as, for example, lockingscrew 624. As described above with respect to valve assembly 600, priorto implantation in a patient the prosthetic valve is crimped to aradially collapsed state. However, the presence of locking mechanism 610and locking screw 624 in the illustrated example of FIG. 18, forexample, can limit the degree to which the prosthetic valve can beradially collapsed. Specifically, the width of locking screw 624 extendsinto the frame profile, which can limit the degree to which the frame604 can be crimped. Since a smaller crimped diameter is preferable forimplantation into a patient, reducing the diameter of the locking screw624 is desirable.

However, the tension force on the screw during valve expansion, thetorque required to rotate the screw, the fatigue tension of the screwduring the lifecycle of the valve, and bending moments due to sideforces on the screw all limit the amount to which the diameter of thelocking screw 624 can be reduced. For example, deformation of the frameduring crimping can exert bending forces on the screw, which can causeplastic deformation of the screw. Thus, incorporating a screw adapted toflex or bend along at least a portion of the screw without permanentdeformation can allow a reduction of the screw diameter along all or aportion of the length of the screw.

The flexible screw 900 in the illustrated embodiment can comprise arelatively rigid threaded portion 902, a relatively flexible portion904, and a screw head 906 connected to the end of the flexible portion,with the flexible portion 904 positioned between the threaded portion902 and the screw head 906. The threaded portion 902 can have anexternally threaded surface. The flexible portion 904 is relatively moreflexible than the rigid threaded portion 902 and therefore can flex orbend relative to the threaded portion. The flexible portion 904 cancomprise, for example, a braided cable, a wire, a laser cut tube, or ahypotube. The threaded portion 902, the flexible portion 904, and thescrew head 906 can be connected together via, for example, laserwelding, a pressed connection, or by integrating and machining them allas one piece. The threaded portion 902, the flexible portion 904, andthe screw head 906 can be made of, for example, titanium (e.g.,Ti-6Al-4V ELI), cobalt-chrome, stainless steel (e.g., 316, 304), PEEK,or other materials.

FIG. 33 shows a portion of an exemplary valve assembly where a lockingscrew 624 is used to lock the frame 604 in a particular expanded state.FIG. 34 shows a portion of an exemplary valve assembly where a flexiblescrew 900 replaces the rigid screw 624. The flexible portion 904 ofscrew 900 can bend and absorb bending forces upon radial expansion andcompression of the frame without permanent or plastic deformation of thescrew. As such, the flexible screw 900 can have a smaller diameter thanis possible with the screw 624. Specifically, the diameter of thethreaded portion 902 of flexible screw 900 can be smaller than thediameter of rigid screw 624. Referring to FIG. 32, in some embodiments,the diameter D1 of the threaded portion 902 can be between 0.3 mm and 1mm, and more desirably, between 0.4 mm and 0.6 mm, with 0.5 mm being aspecific example. In some embodiments, the diameter D2 of the flexibleportion 904 can be between 0.1 mm and 0.6 mm, and more desirably between0.2 mm and 0.4 mm, with 0.3 mm being a specific example. The flexiblescrew 900 otherwise operates in the same manner as the locking screw624.

FIG. 35 shows an exemplary flexible screw 1000, according to anotherembodiment. The screw 1000 comprises a relatively rigid threaded portion1002, a relatively flexible portion 1004 that is more flexible than thethreaded portion, a screw head 1006 connected to the end of the threadedportion, and a stopper 1008. The flexible screw 1000 is similar to theflexible screw 900 except that the threaded portion 1002 is positionedbetween the flexible portion 1004 and the screw head 1006 and theaddition of the stopper 1008 connected to the distal end of the flexibleportion 1004. An advantage of the flexible screw 1000 is that there isno need to transfer torque through the flexible portion 1004 of thescrew 1000 when screwing the screw onto the frame.

FIGS. 36A-36B show a portion of an exemplary valve assembly where theflexible screw 1000 can be used to lock the frame 604 in a particularradially expanded state. In the illustrated example of FIG. 36A, thevalve is shown in an expanded configuration prior to locking the valve.In the illustrated example of FIG. 36B, the valve is shown after it islocked in place using the screw 1000. The example valve assembly ofFIGS. 36A-36B can be manufactured by connecting the stopper 1008 to thescrew 1000 after positioning the screw within the proximal and distalnuts 626, 628. For example, the threaded portion 1002 of the screw 1000could first be screwed into the proximal nut 626, followed by insertingthe flexible portion 1004 of the screw through the distal nut 628. Thestopper 1008 could then be welded or otherwise affixed to the distal endof the flexible portion 1008 to trap the proximal and distal nuts 626,628 between the screw head 1006 and the stopper. Other methods ofmanufacture can also be used to ensure that the nuts 626, 628 arepositioned between the screw head 1006 and the stopper 1008. When theframe 604 is compressed into a crimped configuration prior toimplantation in a patient (e.g., from the configuration shown in FIG.36A), the distal nut 628 is positioned closer to the stopper 1008. Assuch, the flexible portion 1004 must be long enough so that the frame604 can be crimped the desired amount without the distal nut abuttingagainst the stopper.

In the example of FIGS. 36A-36B, the threaded portion 1002 of theflexible screw 1000 can engage internal threads of the proximal nut 626and the flexible portion 1004 can move freely within the distal nut 628in an axial direction. After the frame is expanded (e.g., with one ormore linear actuator assemblies 608 of FIG. 18) to a desired radialexpansion size, as shown in FIG. 36A, the screw 1000 can be used to lockthe frame as described herein. Locking the frame can be accomplished byrotating the screw to move it in a proximal direction with respect tothe nuts 626, 628 (e.g., by rotating the screw in a counter-clockwisedirection). The screw 1000 can be so rotated until the stopper 1008abuts the distal nut 628, as shown in FIG. 36B. From this configuration,further radial expansion of the frame is possible by additionallyforeshortening the frame and reducing the axial distance between theproximal nut 626 and the distal nut 628. However, radial compression ofthe frame is prohibited in the locked configuration of FIG. 36B becausethe threaded portion 1002 being threaded to the proximal nut 626 and thestopper 1008 abutting the distal nut 628 prevent the axial distancebetween the proximal and distal nuts from increasing.

FIGS. 37A-37C show alternative flexible screws 1100, 1200, and 1300.Each of the flexible screws 1100, 1200, 1300 have a relatively rigidthreaded portion 1102, 1202, 1302 respectively, similar to threadedportion 902 of screw 900 and a screw head 1106, 1206, 1306 respectively,similar to screw head 906 of screw 900, connected to the end of theflexible portion opposite the threaded portion. In the example of FIG.37A, the screw 1100 has a flexible portion 1104 comprising a cable(e.g., a welded or pressed braided cable). In the example of FIG. 37B,the screw 1200 has a flexible portion 1204 comprising a solid or tubularshaft having a smaller diameter than that of the threaded portion 1202.The screw 1200 can be manufactured by one part machining (e.g.,machining a solid shaft or hollow tube, such as by laser cutting). Inthe example of FIG. 37C, the screw 1300 has a flexible portion 1304comprising metal hypotube that can be formed, for example, by lasercutting a metal tube.

The flexible screws 900, 1000, 1100, 1200, 1300 can also be used withprosthetic valves that have a rotatable or screw type mechanicalexpansion mechanism, such as prosthetic valve 1800 of FIG. 51, describedin further detail below. In the illustrated example of FIG. 51, screws900 are shown but could be replaced with any of screws 1000, 1100, 1200,or 1300.

Referring to FIG. 51, the prosthetic valve 1800 comprises a frame 1802,which can have the same construction as the frame 602 of FIG. 18, and avalvular structure 1804. In this embodiment, a proximal end portion ofeach screw 900 can be modified to include an attachment member 1806 thatcan include a notch 1808 and a projection 1810 that can releasablycouple to a corresponding projection of a drive shaft of a deliveryapparatus (not shown). The drive shaft can be attached to a motor orother device that can cause it to rotate. When the drive shaft is sorotated while coupled to the attachment member 1806 of a screw 900, thetorque can be transferred to the screw, causing the screw to rotate.

A sleeve 1812 and a nut 1814 can be attached to the frame 1802 ataxially spaced locations. The screw 900 can be fixed axially relative tothe sleeve 1812 while the threaded portion 902 of the screw can engageinternal threads of the nut 1814 such that rotation of the screw 900causes the distance between the attachment locations of the sleeve 1812and the nut 1814 to vary such that the frame 1802 expands or contractsradially, based on the direction of the rotation. The flexible portion904 can extend along the screw at least partially between the sleeve1812 and the nut 1814.

In other examples, the prosthetic valve 1800 can incorporate screws1000, in which case each screw 1000 can be axially fixed to a sleeve1814 (similar to nut 1814 but without internal threads) and the threadedportion 1002 of the screw can engage internal threads of a nut 1812(similar to sleeve 1812 but with internal threads), which also resultsin rotation of the screw causing expansion or contraction of the frame1802. Further details regarding the prosthetic valve 1800 and deliverydevices that can be used to implant the prosthetic valve are disclosedin co-pending U.S. Provisional Appl. No. 62/548,855, which isincorporated herein by reference.

FIG. 38 shows a portion of frame 604 and a locking screw 624 when thescrew is screwed into proximal nut 626 and distal nut 628 to lock theframe in a particular radially expanded state as discussed above inconnection with FIGS. 24A-24D. Utilizing a screw such as the lockingscrew 624 to lock the frame is a robust and simple design due to thehigh tension strength of screws and the low torque required for locking.FIGS. 39-49 show various ways of further locking the position of ascrew, such as the screw 624, under dynamic vibration loads.

FIGS. 39-41 show an example of a locking member comprising a biasedspring lock 1400 that can be affixed to a proximal nut 626 to resistrotation of the locking screw 624 after the locking screw is moved intoa position for retaining the frame 604 in the expanded state. FIG. 39shows the frame 604, the locking screw 624, and the tool head 632 beforethe frame is placed in the locked position. In FIG. 39, the tool head632 is positioned around the screw head 630 (not shown in FIG. 39) suchthat the tool head can be rotated to advance the locking screw 624 to alocked position where the screw head 630 abuts against the proximal nut626.

The spring lock 1400 can be in the form of a leaf spring as shown andcan have a fixed end portion 1402 secured to the nut 626 and a free endportion 1404 that is biased inwardly toward the screw 624 such that itexerts a radially inward directed force towards the locking screw 624.As the tool head 632 is rotated and advanced distally, the shape of thespring lock 1400 is such that the tool head can slide under the free endportion 1404, pushing the spring lock away from the locking screw 624,as shown in FIG. 40. While the tool head 632 is positioned between thescrew 624 and the spring lock 1400, the circular shape of the tool headallows it to be easily rotated despite the presence of the spring locksince very little surface area of the tool head is in contact with thespring lock.

When the tool head 632 has fully advanced the screw head 630 against theproximal nut 630, tool head 632 can be removed from the screw head asshown in FIG. 41. This causes the free end portion 1404 of the springlock 1400 to press against the screw head 630. Due to the flat surfaceof the screw head 630 and the pressure exerted against the screw head bythe spring lock 1400, the torque required to further rotate the screw624 is increased. The pressure exerted by the spring against the screwhead further resists rotation of the screw (and loosening of the screw)against dynamic vibrational loads on the screw. The spring can beselected to have a stiffness sufficient to resist further rotation ofthe screw under the load applied by the user to rotate the screw intothe locked position.

In another example, the spring can be selected to have a stiffness thatwould still allow an operator to rotate the locking screw 624 from itslocked position with a pre-defined torque while still resisting rotationof the screw caused by vibrational loads. In alternative embodiments, aspring lock can be affixed to a location on the frame other than the nut626. For example, a spring lock can be affixed to a strut of the frameat a location where the spring lock can engage the screw head 630.

FIGS. 42-43 show an alternative example of a biased spring lock 1410that can be used to resist rotation of the locking screw 624 after theprosthetic valve is expanded and the locking screw is moved to thelocked position. In the example of FIGS. 42-43, the spring lock 1410 hasa fixed end portion 1412 that is affixed to the screw head 630 ratherthan the proximal nut 626 as in the example of FIGS. 39-41, and a freeend portion 1414. The spring lock 1410 is biased against the nut 626.The spring lock 1410 is configured to be held by the tool head 632 in afirst, non-engaged position away from the nut 626 against the force ofthe spring lock 1410 and when released from the tool head 632, thespring lock can revert to a second, engaged position with the free endportion 1414 bearing against the nut 626.

FIG. 42 shows the frame 604 and the locking screw 624 as the tool head632 is in position to rotate the locking screw into a locked positionabutting against the proximal nut 626. As shown, the tool head 632 caninclude a slot or opening 1416 sized to receive the free end portion ofthe spring lock and hold it in the non-engaged position. After the screwhead 630 is moved into a locked position abutting against the proximalnut 626, the tool head 632 can be removed from the screw head as shownin FIG. 43 (and as previously described). This causes the spring lock1410 to be released from the tool head 632 and causes the spring lock tospring back and press against the proximal nut 626. The spring lockexerts sufficient pressure against the nut 626 to resist rotation of thescrew 624 caused by vibrational loads. The nut 626 can be formed with aflattened surface 627 that is contacted by the spring lock to enhanceresistance against rotation of the screw.

FIGS. 44-45 show an example of a plastically deformable locking member1500 that can be used to resist rotation of the locking screw 624. Thelocking member 1500 in the illustrated configuration comprises abendable flange that is fixed at one end to the screw head 630. FIG. 44shows the screw 624 in a locked position with the screw head 630abutting against the proximal nut 626. Once the screw head 630 is inplace, the locking member 1500 can be bent against the proximal nut 626by an external force as shown in FIG. 45. The locking member 1500 isplastically deformed when bent and therefore retains its shape againstor adjacent the nut 626. Once the locking member 1500 is bent into theposition as shown in FIG. 45, the locking member 1500 resists rotationof the locking screw 624 caused by random vibrational forces.

The locking member 1500 can have a flat profile that corresponds to theflat surface 627 of the nut 626. However, the locking member and/or thenut can have other shapes in alternative embodiments. For example, thelocking member 1500 can be sized and shaped to be received in acorrespondingly shaped recess or opening in the nut.

The locking member 1500 can be bent by the locking tool 632 (not shownin FIGS. 44-45) by, for example, pushing the locking tool or a separatepushing member against the flange while the screw head is abuttedagainst the proximal nut 626. In other examples, other methods ofbending the flange 1500 can be used. The locking member can comprise aplastically deformable material, such as stainless steel, and can beformed as part of the screw head 630 or separately formed and attached(e.g., by welding) to the screw head. In alternative embodiments, thelocking member can be affixed to the nut 626 or at another convenientlocation of the frame and is then bent against the screw head 630 toresist rotation of the screw.

In particular embodiments, a valve assembly can incorporate a ratchetlock system configured to permit rotation of a locking screw in onedirection to place the screw in a locked position and resist rotation ofthe screw in the opposite direction. FIG. 46 shows an example of aratchet lock 1600 configured to resist rotation of the screw 624 afterthe screw is placed in a locked position after valve expansion. Theratchet lock 1600 in the illustrated embodiment is attached to theproximal end of a proximal nut 626 and positioned to engage the screwhead 630. In some implementations, the proximal nut 626 and the ratchetlock 1600 can be manufactured as a single piece. In otherimplementations, the ratchet lock 1600 can be separately formed and thenattached to the nut 626 (e.g., by welding). In still otherimplementations, the ratchet lock 1600 can be mounted to the frame 604apart from the nut 626; that is, the ratchet lock 1600 need not bemounted directly on the nut as long as it is positioned to engage thescrew head 630. The ratchet lock 1600 is formed with one or moreratcheting features that are configured to engage the screw head 630 andallow rotation of the locking screw 624 in one direction to allow a userto move the locking screw to its locked position but resist rotation ofthe locking screw in the opposition direction.

FIGS. 47A-47D show various views of the proximal nut 626 and theattached ratchet lock 1600. The ratchet lock 1600 in the illustratedconfiguration can have a base member 1602 and one or more ratchetingfeatures in the form of one or more ratchet teeth 1604 extending fromthe base member 1602. As best shown in FIG. 47D, the ratchet teeth 1604can be positioned on opposite corners of the base member 1602 andproject outwardly from the base member and have angled surfaces thatengage the screw head 630.

The spacing between the teeth 1604 can be slightly greater than thewidth of the screw head 630. In use, as the locking screw 624 is rotatedtoward its locked position (e.g., in a clockwise direction), the screwhead 630 will come in contact with the teeth 1604. Due to the angledsurfaces of the teeth 1604, the screw head can be further rotated in thesame direction toward the locked position until the screw head ispositioned between the teeth 1604, as depicted in FIG. 46. The teeth1604 can be sized and shaped such that a predetermined torque applied tothe screw by the user allows the screw to be placed in its lockedposition. Once the screw head 630 is between the teeth, rotation of thescrew head (and therefore the locking screw) in the opposite direction(e.g., counterclockwise) is resisted by the contact between teeth andthe screw head. In this manner, the ratchet lock 1600 resists rotationalmovement of the locking screw 624 that can be caused by vibrationalforces.

Although two ratchet teeth are shown in the illustrated embodiment, afewer or greater number of teeth can be used. Also, in alternativeembodiments, the screw head 630 can be formed with one or moreratcheting features (e.g., teeth 1604) that engage an adjacent surfaceof the nut 626 or another component of the frame (without using theratchet lock 1600). In some embodiments, one or more ratcheting featureson the screw head can be adapted to engage one or more ratchetingfeatures on a ratchet lock 1600 or on another component of the frame.

FIG. 48 shows an example of a “click lock” system that can be used toresist rotation of the locking screw 24 after it is placed in a lockedposition. The exemplary click lock system of FIG. 48 is the same as theexemplary ratchet lock system of FIG. 46 except that the ratchet lock1600 is replaced with click lock 1650, which in the illustratedconfiguration comprises a base member 1652 and one or more teeth orprojections 1654, 1656. As described above with respect to the ratchetlock 1600, the click lock 1650 can be integrally formed as part of thenut 626, or it can be a separate component mounted on the nut or onanother location on the frame 604.

FIGS. 49A-49D show various views of a proximal nut 626 and the attachedclick lock 1650. As best shown in FIG. 49D, each of the teeth has aconvex surface projecting outwardly from the base member 1652. The teeth1654 are sized and shaped to permit rotation of the screw head in bothdirections when a predetermined torque is applied to the screw by theuser. In the illustrated example, upon application of a predeterminedtorque to the screw, the screw head 630 can rotate over the surfaces ofthe teeth 1654 in both directions causing a “click” with every 90degrees of rotation. However, the engagement of the teeth with the screwhead will resist rotation of the screw if the predetermined torque isnot exceeded. In this manner, rotational movement of the screw caused byvibrational loads can be resisted.

It should be understood that the click lock need not make an audibleclicking noise when rotated. In the context of the present disclosure, aclick lock provides resistance against rotation at one or morerotational orientations of the click lock relative to the componentengaging the click lock (e.g., the screw head), or vice versa. When therotated component overcomes the resistance, the torque required torotate that component decreases. The increasing and decreasingresistance against torqueing of the screw can provide tactile feedbackto the user as to the rotational orientation of the screw, which canfeel like the screw is “clicking” as it is rotated.

Any of the locking mechanisms discussed above in connection with FIGS.39-49 can be used to apply resistance against rotation of a screw thatis used to produce radial expansion and compression of the frame of aprosthetic valve. For example, any of these locking mechanisms can beused in connection with the screws 900 in the prosthetic valve 1800 ofFIG. 51.

FIG. 50 shows alternative embodiment of a frame 1700 and a skirt 1702 ofa prosthetic heart valve. The skirt 1702 can be constructed from any ofthe materials described above in connection with skirt 50 of FIG. 2. Theskirt 1702 can function as a sealing member to help establish a sealwith surrounding tissue, similar to the skirt 50. The skirt 1702 canalso help secure a leaflet assembly (e.g., leaflet assembly 48) insidethe frame, such as by suturing the inflow edges of the leaflets to theskirt 802.

The frame 1700 can be constructed similarly to frame 22 of FIG. 2. Theframe 1700 can have a plurality of diagonally extending, parallel struts1704, 1706, and 1708 that are pivotably connected to struts that extendperpendicularly to the struts 1704, 1706, 1708, similar to frame 22 ofFIG. 2 and frame 200 of FIG. 4. For purposes of illustration, only threestruts 1704, 1706, 1708 of the frame are shown.

The skirt 1702 can be supported on the frame 1700 by weaving the skirtthrough the struts 1704, 1706, 1708 of the frame such that portions ofthe skirt are positioned on the inner surfaces of struts and portions ofthe skirt are positioned on the outer surfaces of the struts. Forexample, in the illustrated embodiment, the skirt 1702 is positioned onthe inner surfaces of struts 1704, 1708 and on the outer surface ofstruts 1706. Alternatively, the skirt 1702 can be positioned on theouter surface of struts 1704, 1708 and on the inner surface of struts1706.

The struts of the frame 1700 can be connected together using fasteners,such as fasteners 40 of FIG. 2. The skirt 1702 can be placed between thestruts during the process of assembling the struts to form the frame. Inthe illustrated embodiment of FIG. 27, the fasteners used to connect thestruts of frame 1700 together can extend through the skirt 1702 to holdthe skirt in place on the struts without the use of sutures. Forexample, the skirt 1702 can be formed with pre-formed holes sized toreceive the fasteners 40, or alternatively, the fasteners can be pressedthrough and puncture the skirt material during the assembly process. Inlieu of or in addition to the use of the fasteners, sutures can be usedto secure the skirt 1702 to the frame 1700.

Further examples:

1. A prosthetic valve delivery assembly, comprising:

a prosthetic valve comprising a radially expandable and compressibleexpandable frame and a plurality of locking units coupled to the frameat circumferentially spaced locations, each locking unit comprising arespective first coupling member and a locking member; and

a delivery apparatus comprising:

a plurality of elongate positioning members, each of the positioningmembers comprising a respective second coupling member at a distal endthereof, each second coupling member being releasably coupled to arespective first coupling member;

a plurality of elongate actuation members, each of the actuation membershaving a distal end portion coupled to the frame; and

a plurality of release members, each of the plurality of release memberscoaxially disposed with respect to, and engaged with, one of the lockingunits;

wherein moving the positioning members or the actuation members axiallyrelative to one another causes the frame to expand or contract, andretracting the release members proximal to the locking members of thelocking units causes the locking members to move to a locked position toresist contraction of the frame and retracting the release membersproximal to the first coupling members of the locking units causes thefirst coupling members to decouple from the second coupling members,thereby permitting the positioning members to decouple from the lockingunits.

2. The delivery assembly of example 1, further comprising a handlecoupled to proximal end portions of the first and second actuationmembers, the handle comprising a first actuator configured to produceaxial movement of the positioning members.

3. The delivery assembly of example 2, wherein the handle comprises asecond actuator configured to produce axial movement of the releasemembers relative to the positioning members and the actuation members.

4. The delivery assembly of any preceding example, wherein each of thelocking members comprises a pair of deflectable locking jaws disposedabout one of the actuation members.

5. The delivery assembly of any preceding example, wherein each of thefirst coupling members comprises a tab and a notch and each of thesecond coupling member comprises a tab and a notch, the tab of the firstcoupling member received in the notch of the second coupling member andthe tab of the second coupling member received in the notch of the firstcoupling member.

6. The delivery assembly of example 5, wherein the tab of the secondcoupling member comprises an axially extending slot.

7. The delivery assembly of example 1, wherein the actuation memberscomprise a plurality of tethers.

8. The delivery assembly of any preceding example, further comprising aplurality of cutting members configured to sever the actuation membersat locations proximal to the locking units.

9. The delivery apparatus of any one of examples 1-8, wherein each ofthe actuation members comprises a plurality of longitudinally spacedapart protrusions configured to engage one of the locking members of oneof the locking units.

10. The delivery assembly of any preceding example, wherein each of thelocking units comprises an elongate first member coupled to a proximalend of the frame and an elongate second member coupled to a distal endof the frame, the first and second members being axially moveablerelative to each other.

11. The delivery assembly of example 10, wherein each of the firstmembers of the locking units is releasably coupled to one of thepositioning members and each of the second members is releasably coupledto one of the actuation members.

12. The delivery assembly of example 11, wherein retracting the releasemembers proximal to the locking units is effective to decouple thesecond members of the locking units from the actuation members.

13. The delivery assembly of any of examples 10-12, wherein each of thefirst members of the locking units comprises a first locking feature andeach of the second members of the locking units comprises a secondlocking feature, and retracting the release members proximal to thelocking units causes the first locking feature to engage the secondlocking feature to resist relative axial movement between the first andsecond members and contraction of the frame.

14. The delivery assembly of example 13, wherein each of the firstlocking features comprises a deflectable locking bar and each of thesecond locking features comprises at least one aperture sized to receivea locking bar.

15. The delivery assembly of any of examples 10-14, wherein the firstmember of each locking unit is pivotably connected to an apex at theproximal end of the frame and the second member of each locking unit ispivotably connected to an apex at the distal end of the frame.

16. The delivery assembly of any preceding example, wherein the framecomprises a plurality of interconnected struts having a plurality oflinear segments that are laterally offset from each other in a directionperpendicular to the lengths of the struts.

17. The delivery assembly of example 16, wherein the struts areconnected to each other at locations between the linear segments.

18. The delivery assembly of example 17, wherein the struts arehingeably coupled to each other by pins extending through the struts atthe locations between the linear segments.

19. The delivery assembly of any one of examples 1-9 and 16-18, whereineach of the actuation members extends coaxially through one of thepositioning members.

20. The delivery assembly of any one of examples 1-9 and 16-18, whereineach of the release members extends through one of the locking units andcoaxially between one of the positioning members and one of theactuation members.

21. The delivery assembly of any one of examples 1-9 and 16-18, whereinthe first coupling member of each of the plurality of locking unitscomprises a radially-outwardly biased fin and wherein each of therelease members is disposed about a positioning member and a firstcoupling member.

22. A prosthetic valve comprising:

a radially expandable and compressible frame comprising a plurality ofinterconnected struts, each strut having a first end, a second end, anda length extending from the first end to the second end, each strutcomprising a plurality of linear segments that are laterally offset fromeach other in a direction perpendicular to the lengths of the struts;and

a valvular structure mounted to the frame and configured to regulate theflow of blood through the prosthetic valve.

23. The prosthetic valve of example 22, wherein each of the plurality ofstruts is hingeably connected to at least another of the plurality ofstruts.

24. The prosthetic valve of example 22 or 23, further comprising aspacer disposed between a pair of connected struts.

25. The prosthetic valve of any of examples 22-24, wherein the strutsare connected to each other by pins extending through the struts.

26. The prosthetic valve of any of examples 22-25, wherein the framecomprises a plurality of circumferentially spaced locking unitsconfigured to lock the frame in a radially expanded state.

27. A method of delivering a prosthetic valve, the method comprising:

inserting a distal end of an elongate delivery apparatus into a patient,the elongate delivery apparatus releasably coupled to the prostheticvalve, the prosthetic valve comprising an expandable frame comprising aplurality of locking units;

axially moving a plurality of elongate positioning members of thedelivery apparatus to expand the prosthetic valve to an expanded stateof a desired size;

removing a plurality of elongate release members from the plurality oflocking units, causing the positioning members to decouple from theframe and the locking units to lock the frame in the expanded state; and

removing the elongate delivery apparatus from the patient.

28. The method of example 27, wherein removing the release members fromthe locking units allows first coupling members of the actuation membersto decouple from corresponding second coupling members of the lockingunits.

29. The method of example 27 or 28, wherein:

axially moving a plurality of elongate actuation members of the deliveryapparatus comprises axially moving a first plurality of actuationmembers relative to a second plurality of actuation members of thedelivery apparatus to expand the prosthetic valve; and

removing the release members from the locking units allows the first andsecond actuation members to decouple from the frame.

30. An assembly comprising:

a prosthetic valve comprising a radially expandable and compressibleannular frame;

at least one linear actuator assembly coupled to the frame andconfigured to apply a distally directed force and/or a proximallydirected force to the frame to radially expand or compress the frame;and

at least one locking mechanism coupled to the frame comprising a firstsleeve member connected to the frame at a first location, a secondsleeve member having internal threads and being connected to the frameat a second location, and a first screw configured to engage theinternal threads of the second sleeve member to retain the frame in aradially expanded state.

31. The assembly of example 30, wherein the at least one linear actuatorassembly is releasably coupled to the frame.

32. The assembly of example 30, wherein the at least one linear actuatorassembly comprises an actuator member configured to be releasablycoupled to the frame.

33. The assembly of example 32, wherein the at least one linear actuatorassembly comprises a first threaded member connected to a distal endportion of the actuator member, the first threaded member beingconfigured to releasably engage a second threaded member connected tothe frame.

34. The assembly of example 33, wherein the first threaded membercomprises a second screw and the second threaded member comprises aninternally threaded nut.

35. The assembly of any of examples 32-34, wherein the actuator membercomprises a cable.

36. The assembly of any of examples 32-35, wherein the at least onelinear actuator assembly further comprises a sleeve positioned annularlyaround the actuator member.

37. The assembly of any of examples 32-36, further comprising:

an annular stopper connected to the frame, wherein the actuator memberextends through the stopper;

wherein the at least one linear actuator assembly comprises a supporttube positioned annularly around the actuator member and the stopper isconfigured to engage a distal end of the support tube and prevent thesupport tube from moving distally beyond the stopper in an axialdirection.

38. The assembly of any of examples 30-37, further comprising a lockingtool configured to be releasably coupled to the first screw, the lockingtool comprising a tool head configured to engage and produce rotation ofthe first screw when the locking tool is coupled to the first screw suchthat the first screw moves axially through the first sleeve member andthe second sleeve member.

39. The assembly of example 38, wherein the first screw has a screw headat its proximal end and wherein a shape of the tool head is configuredto correspond to a shape of the screw head such that the tool head isoperable to couple with the screw head such that rotation of the toolhead causes rotation of the first screw.

40. The assembly of example 39, wherein the screw head and the firstsleeve member are configured such that the screw head is prevented frommoving distally beyond the first sleeve member in an axial direction.

41. The assembly of any of examples 38-40, wherein the at least onelocking mechanism further comprises an inner shaft extending partlywithin a lumen of the tool head, the inner shaft having a threadedsurface at its distal end, the screw head having internal threads, andthe inner shaft being configured such that its threaded surface engagesthe internal threads of the screw head.

42. The assembly of any of examples 39-41, wherein the first screwfurther comprises a rigid portion and a flexible portion positionedbetween the screw head and the rigid portion.

43. The assembly of example 42, wherein the flexible portion of thefirst screw comprises braded cable.

44. The assembly of example 42, wherein the flexible portion of thefirst screw comprises hypotube.

45. The assembly of any of examples 39-41, wherein the first screwfurther comprises a rigid portion connected to the screw head, aflexible portion connected to a distal end of the rigid portion, and astopper connected to a distal end of the flexible portion.

46. The assembly of any of examples 39-45, further comprising a springlock attached to the first sleeve member, wherein the spring lock isconfigured to exert a radially inward directed force against the screwhead to resist rotation of the screw.

47. The assembly of any of examples 39-45, further comprising a springlock attached to the screw head, wherein the spring lock is configuredto exert a radially inward directed force against the first sleevemember to resist rotation of the screw.

48. The assembly of any of examples 39-45, further comprising a flangeattached to the screw head, wherein the flange is configured to bendagainst the first sleeve member to resist rotation of the screw.

49. The assembly of any of examples 39-45, further comprising a ratchetlock attached to a proximal end of the first sleeve member, wherein theratchet lock comprises teeth configured to allow rotation of the screwhead in a first direction and prevent rotation of the screw head in asecond direction.

50. The assembly of any of examples 39-45, further comprising a clicklock attached to a proximal end of the first sleeve member, wherein theclick lock comprises teeth configured to resist rotation of the screw byan amount less than 90 degrees and to click when the screw is rotated 90degrees.

51. An assembly comprising:

a prosthetic valve comprising a radially expandable and compressibleannular frame; and at least one expansion and locking mechanismcomprising:

-   -   a linear actuator connected to the frame, wherein the linear        actuator is configured to apply a distally directed force and/or        a proximally directed force to the frame to radially expand or        compress the frame; and    -   a rotating member coaxially positioned relative to the linear        actuator configured to retain the frame in a radially expanded        state.

52. The assembly of example 51, further comprising:

a first sleeve member connected to the frame at a first location; and

a second sleeve member having internal threads and being connected tothe frame at a second location;

wherein the linear actuator is releasably coupled to the frame;

wherein the rotating member is a screw configured to engage the internalthreads of the second sleeve member; and

wherein the linear actuator extends through a lumen of the screw.

53. The assembly of example 52, further comprising a locking tool thatis configured to be releasably coupled to the screw and rotate the screwsuch that the screw moves axially through the first sleeve member andthe second sleeve member when the locking tool is coupled to the screw.

54. The assembly of example 53, wherein the locking tool and the firstsleeve member are configured such that the locking tool is preventedfrom moving distally beyond the first threaded member in an axialdirection.

55. The assembly of any of examples 52-54, wherein the screw has a screwhead at its proximal end and wherein the screw head and the first memberare configured such that the screw head is prevented from movingdistally beyond the first sleeve member in an axial direction

56. The assembly of example 51, wherein the linear actuator is anactuator screw having external threads and is connected to the frame ata first location;

wherein the assembly further comprises a sleeve connected to the frameat a second location;

wherein the actuator screw extends through a lumen of the sleeve;

wherein the rotating member is a locking nut having internal threadsconfigured to engage the threads of the actuator screw; and

wherein the sleeve and the locking nut are configured such that thelocking nut is prevented from moving distally beyond the sleeve in anaxial direction.

57. The assembly of example 56, wherein the actuator screw comprises afirst portion and a second portion, wherein a diameter of the secondportion is less than a diameter of the first portion.

58. The assembly of example 57, wherein the assembly further comprisesan annular actuator member having internal threads configured to engagethe threads of the second portion of the actuator screw such that whenthe internal threads of the actuator member are engaged with the threadsof the second portion of the actuator screw, axial movement of theactuator member results in axial movement of the actuator screw.

59. The assembly of any of examples 57-58, further comprising a lockingtool positioned within a lumen of the sleeve, wherein the locking toolhas a notched portion at its distal end configured to engage acorresponding notched portion at a proximal end of the locking nut suchthat rotation of the locking tool in a clockwise direction causesrotation of the locking nut in a clockwise direction.

60. The assembly of example 59, wherein the locking tool has aninternally threaded surface to engage the threads of the actuator screw.

61. The assembly of example 59, further comprising a support tubepositioned annularly around the locking tool, wherein a proximal end ofthe sleeve is configured to engage a distal end of the support tube suchthat the support tube is prevented from moving distally beyond theproximal end of the sleeve in an axial direction.

62. The assembly of any of examples 30-61, further comprising a skirt,wherein the frame comprises a plurality of rows of struts, and whereinthe skirt is positioned inside of at least one row of struts and outsideof at least another row of struts.

63. An implantable prosthetic valve comprising:

an annular frame comprising a plurality of rows of struts and beingradially collapsible and expandable between a radially collapsedconfiguration and a radially expanded configuration; and

a skirt weaved around the struts such that the skirt is positionedinside of at least one row of struts and outside of at least another rowof struts.

64. A method of implanting a prosthetic heart valve, the methodcomprising:

inserting the prosthetic heart valve into a patient's vasculature, theprosthetic heart valve being coupled to a distal end portion of a linearactuator, wherein the prosthetic heart valve comprises a frame in aradially compressed state;

actuating the linear actuator to expand the frame to a radially expandedstate; and

rotating a screw to advance the screw through first and second memberson the frame to retain the prosthetic valve in the radially expandedstate.

65. The method of example 64, wherein the act of rotating the screwcomprises rotating a locking tool coupled to the screw, and thende-coupling the locking tool from the screw after the screw is advancedthrough the first and second members.

66. The method of any of examples 64-65, further comprising de-couplingthe linear actuator from the frame.

67. The method of example 66, wherein the act of de-coupling the linearactuator comprises unscrewing a threaded portion of the linear actuatorfrom a corresponding threaded portion of the frame.

68. The method of any of examples 64-67, wherein the act of actuatingthe linear actuator comprises applying a proximally directed force to adistal portion of the frame with a cable.

GENERAL CONSIDERATIONS

It should be understood that the disclosed embodiments can be adapted todeliver and implant prosthetic devices in any of the native annuluses ofthe heart (e.g., the pulmonary, mitral, and tricuspid annuluses), andcan be used with any of various delivery approaches (e.g., retrograde,antegrade, transseptal, transventricular, transatrial, etc.). Thedisclosed embodiments can also be used to implant prostheses in otherlumens of the body. Further, in addition to prosthetic valves, thedelivery assembly embodiments described herein can be adapted to deliverand implant various other prosthetic devices such as stents and/or otherprosthetic repair devices.

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedisclosed methods, apparatus, and systems should not be construed asbeing limiting in any way. Instead, the present disclosure is directedtoward all novel and nonobvious features and aspects of the variousdisclosed embodiments, alone and in various combinations andsub-combinations with one another. The methods, apparatus, and systemsare not limited to any specific aspect or feature or combinationthereof, nor do the disclosed embodiments require that any one or morespecific advantages be present or problems be solved. The technologiesfrom any example can be combined with the technologies described in anyone or more of the other examples. In view of the many possibleembodiments to which the principles of the disclosed technology may beapplied, it should be recognized that the illustrated embodiments areonly preferred examples and should not be taken as limiting the scope ofthe disclosed technology.

Although the operations of some of the disclosed embodiments aredescribed in a particular, sequential order for convenient presentation,it should be understood that this manner of description encompassesrearrangement, unless a particular ordering is required by specificlanguage set forth below. For example, operations described sequentiallymay in some cases be rearranged or performed concurrently. Moreover, forthe sake of simplicity, the attached figures may not show the variousways in which the disclosed methods can be used in conjunction withother methods. Additionally, the description sometimes uses terms like“provide” or “achieve” to describe the disclosed methods. These termsare high-level abstractions of the actual operations that are performed.The actual operations that correspond to these terms may vary dependingon the particular implementation and are readily discernible by one ofordinary skill in the art.

As used in this application and in the claims, the singular forms “a,”“an,” and “the” include the plural forms unless the context clearlydictates otherwise. Additionally, the term “includes” means “comprises.”Further, the terms “coupled” and “associated” generally meanelectrically, electromagnetically, and/or physically (e.g., mechanicallyor chemically) coupled or linked and does not exclude the presence ofintermediate elements between the coupled or associated items absentspecific contrary language.

As used herein, the term “proximal” refers to a position, direction, orportion of a device that is closer to the user and further away from theimplantation site. As used herein, the term “distal” refers to aposition, direction, or portion of a device that is further away fromthe user and closer to the implantation site. Thus, for example,proximal motion of a device is motion of the device toward the user,while distal motion of the device is motion of the device away from theuser. The terms “longitudinal” and “axial” refer to an axis extending inthe proximal and distal directions, unless otherwise expressly defined.

As used herein, the terms “integrally formed” and “unitary construction”refer to a construction that does not include any welds, fasteners, orother means for securing separately formed pieces of material to eachother.

As used herein, operations that occur “simultaneously” or “concurrently”occur generally at the same time as one another, although delays in theoccurrence of one operation relative to the other due to, for example,spacing, play or backlash between components in a mechanical linkagesuch as threads, gears, etc., are expressly within the scope of theabove terms, absent specific contrary language.

In view of the many possible embodiments to which the principles of thedisclosure may be applied, it should be recognized that the illustratedembodiments are only preferred examples and should not be taken aslimiting the scope of the disclosure. Rather, the scope of thedisclosure is defined by the following claims.

What is claimed is:
 1. A prosthetic valve comprising: a radiallyexpandable and compressible frame comprising a plurality ofinterconnected struts, each strut having a first end, a second end, anda length extending from the first end to the second end, each strutcomprising a plurality of linear segments that are laterally offset fromeach other in a direction perpendicular to the lengths of the struts;and a valvular structure mounted to the frame and configured to regulatethe flow of blood through the prosthetic valve.
 2. The prosthetic valveof claim 1, wherein each of the plurality of struts is hingeablyconnected to at least another of the plurality of struts.
 3. Theprosthetic valve of claim 1, further comprising a spacer disposedbetween a pair of connected struts.
 4. The prosthetic valve of claim 1,wherein the struts are connected to each other by pins extending throughthe struts.
 5. The prosthetic valve of claim 1, wherein the framecomprises a plurality of circumferentially spaced locking unitsconfigured to lock the frame in a radially expanded state.
 6. Anassembly comprising: a prosthetic valve comprising a radially expandableand compressible annular frame; at least one linear actuator assemblycoupled to the frame and configured to apply a distally directed forceand/or a proximally directed force to the frame to radially expand orcompress the frame; and at least one locking mechanism coupled to theframe comprising a first sleeve member connected to the frame at a firstlocation, a second sleeve member having internal threads and beingconnected to the frame at a second location, and a first screwconfigured to engage the internal threads of the second sleeve member toretain the frame in a radially expanded state.
 7. The assembly of claim6, wherein the at least one linear actuator assembly comprises anactuator member configured to be releasably coupled to the frame.
 8. Theassembly of claim 7, wherein the at least one linear actuator assemblycomprises a first threaded member connected to a distal end portion ofthe actuator member, the first threaded member being configured toreleasably engage a second threaded member connected to the frame. 9.The assembly of claim 8, wherein the first threaded member comprises asecond screw and the second threaded member comprises an internallythreaded nut.
 10. The assembly of claim 7, wherein the at least onelinear actuator assembly further comprises a sleeve positioned annularlyaround the actuator member.
 11. The assembly of claim 7, furthercomprising: an annular stopper connected to the frame, wherein theactuator member extends through the stopper; wherein the at least onelinear actuator assembly comprises a support tube positioned annularlyaround the actuator member and the stopper is configured to engage adistal end of the support tube and prevent the support tube from movingdistally beyond the stopper in an axial direction.
 12. The assembly ofclaim 6, further comprising a locking tool configured to be releasablycoupled to the first screw, the locking tool comprising a tool headconfigured to engage and produce rotation of the first screw when thelocking tool is coupled to the first screw such that the first screwmoves axially through the first sleeve member and the second sleevemember.
 13. The assembly of claim 12, wherein the first screw has ascrew head at its proximal end and wherein a shape of the tool head isconfigured to correspond to a shape of the screw head such that the toolhead is operable to couple with the screw head such that rotation of thetool head causes rotation of the first screw.
 14. The assembly of claim13, wherein the screw head and the first sleeve member are configuredsuch that the screw head is prevented from moving distally beyond thefirst sleeve member in an axial direction.
 15. The assembly of claim 12,wherein the at least one locking mechanism further comprises an innershaft extending partly within a lumen of the tool head, the inner shafthaving a threaded surface at its distal end, the screw head havinginternal threads, and the inner shaft being configured such that itsthreaded surface engages the internal threads of the screw head.
 16. Theassembly of claim 6, wherein the frame comprises a plurality ofinterconnected struts, each strut having a first end, a second end, anda length extending from the first end to the second end, each strutcomprising a plurality of linear segments that are laterally offset fromeach other in a direction perpendicular to the lengths of the struts.17. An assembly comprising: a prosthetic valve comprising a radiallyexpandable and compressible annular frame; and at least one expansionand locking mechanism comprising: a linear actuator connected to theframe, wherein the linear actuator is configured to apply a distallydirected force and/or a proximally directed force to the frame toradially expand or compress the frame; and a rotating member coaxiallypositioned relative to the linear actuator configured to retain theframe in a radially expanded state.
 18. The assembly of claim 17,further comprising: a first sleeve member connected to the frame at afirst location; and a second sleeve member having internal threads andbeing connected to the frame at a second location; wherein the linearactuator is releasably coupled to the frame; wherein the rotating memberis a screw configured to engage the internal threads of the secondsleeve member; and wherein the linear actuator extends through a lumenof the screw.
 19. The assembly of claim 18, further comprising a lockingtool that is configured to be releasably coupled to the screw and rotatethe screw such that the screw moves axially through the first sleevemember and the second sleeve member when the locking tool is coupled tothe screw.
 20. The assembly of claim 19, wherein the locking tool andthe first sleeve member are configured such that the locking tool isprevented from moving distally beyond the first threaded member in anaxial direction.
 21. The assembly of claim 18, wherein the screw has ascrew head at its proximal end and wherein the screw head and the firstmember are configured such that the screw head is prevented from movingdistally beyond the first sleeve member in an axial direction
 22. Theassembly of claim 17, wherein the linear actuator is an actuator screwhaving external threads and is connected to the frame at a firstlocation; wherein the assembly further comprises a sleeve connected tothe frame at a second location; wherein the actuator screw extendsthrough a lumen of the sleeve; wherein the rotating member is a lockingnut having internal threads configured to engage the threads of theactuator screw; and wherein the sleeve and the locking nut areconfigured such that the locking nut is prevented from moving distallybeyond the sleeve in an axial direction.
 23. The assembly of claim 22,wherein the actuator screw comprises a first portion and a secondportion, wherein a diameter of the second portion is less than adiameter of the first portion.
 24. The assembly of claim 23, wherein theassembly further comprises an annular actuator member having internalthreads configured to engage the threads of the second portion of theactuator screw such that when the internal threads of the actuatormember are engaged with the threads of the second portion of theactuator screw, axial movement of the actuator member results in axialmovement of the actuator screw.
 25. The assembly of claim 22, furthercomprising a locking tool positioned within a lumen of the sleeve,wherein the locking tool has a notched portion at its distal endconfigured to engage a corresponding notched portion at a proximal endof the locking nut such that rotation of the locking tool in a clockwisedirection causes rotation of the locking nut in a clockwise direction.26. The assembly of claim 25, wherein the locking tool has an internallythreaded surface to engage the threads of the actuator screw.
 27. Theassembly of claim 25, further comprising a support tube positionedannularly around the locking tool, wherein a proximal end of the sleeveis configured to engage a distal end of the support tube such that thesupport tube is prevented from moving distally beyond the proximal endof the sleeve in an axial direction.
 28. The assembly of claim 17,wherein the frame comprises a plurality of interconnected struts, eachstrut having a first end, a second end, and a length extending from thefirst end to the second end, each strut comprising a plurality of linearsegments that are laterally offset from each other in a directionperpendicular to the lengths of the struts